text: """Create portable serialized representations of Python objects.
  
  See module copyreg for a mechanism for registering custom picklers.
  See module pickletools source for extensive comments.
  
  Classes:
  
      Pickler
      Unpickler
  
  Functions:
  
      dump(object, file)
      dumps(object) -> string
      load(file) -> object
      loads(string) -> object
  
  Misc variables:
  
      __version__
      format_version
      compatible_formats
  
  """
  
  from types import FunctionType
  from copyreg import dispatch_table
  from copyreg import _extension_registry, _inverted_registry, _extension_cache
  from itertools import islice
  from functools import partial
  import sys
  from sys import maxsize
  from struct import pack, unpack
  import re
  import io
  import codecs
  import _compat_pickle
  
  from _pickle import PickleBuffer
  
  __all__ = ["PickleError", "PicklingError", "UnpicklingError", "Pickler",
             "Unpickler", "dump", "dumps", "load", "loads", "PickleBuffer"]
  
  # Shortcut for use in isinstance testing
  bytes_types = (bytes, bytearray)
  
  # These are purely informational; no code uses these.
  format_version = "4.0"                  # File format version we write
  compatible_formats = ["1.0",            # Original protocol 0
                        "1.1",            # Protocol 0 with INST added
                        "1.2",            # Original protocol 1
                        "1.3",            # Protocol 1 with BINFLOAT added
                        "2.0",            # Protocol 2
                        "3.0",            # Protocol 3
                        "4.0",            # Protocol 4
                        "5.0",            # Protocol 5
                        ]                 # Old format versions we can read
  
  # This is the highest protocol number we know how to read.
  HIGHEST_PROTOCOL = 5
  
  # The protocol we write by default.  May be less than HIGHEST_PROTOCOL.
  # Only bump this if the oldest still supported version of Python already
  # includes it.
  DEFAULT_PROTOCOL = 4
  
  class PickleError(Exception):
      """A common base class for the other pickling exceptions."""
      pass
  
  class PicklingError(PickleError):
      """This exception is raised when an unpicklable object is passed to the
      dump() method.
  
      """
      pass
  
  class UnpicklingError(PickleError):
      """This exception is raised when there is a problem unpickling an object,
      such as a security violation.
  
      Note that other exceptions may also be raised during unpickling, including
      (but not necessarily limited to) AttributeError, EOFError, ImportError,
      and IndexError.
  
      """
      pass
  
  # An instance of _Stop is raised by Unpickler.load_stop() in response to
  # the STOP opcode, passing the object that is the result of unpickling.
  class _Stop(Exception):
      def __init__(self, value):
          self.value = value
  
  # Jython has PyStringMap; it's a dict subclass with string keys
  try:
      from org.python.core import PyStringMap
  except ImportError:
      PyStringMap = None
  
  # Pickle opcodes.  See pickletools.py for extensive docs.  The listing
  # here is in kind-of alphabetical order of 1-character pickle code.
  # pickletools groups them by purpose.
  
  MARK           = b'('   # push special markobject on stack
  STOP           = b'.'   # every pickle ends with STOP
  POP            = b'0'   # discard topmost stack item
  POP_MARK       = b'1'   # discard stack top through topmost markobject
  DUP            = b'2'   # duplicate top stack item
  FLOAT          = b'F'   # push float object; decimal string argument
  INT            = b'I'   # push integer or bool; decimal string argument
  BININT         = b'J'   # push four-byte signed int
  BININT1        = b'K'   # push 1-byte unsigned int
  LONG           = b'L'   # push long; decimal string argument
  BININT2        = b'M'   # push 2-byte unsigned int
  NONE           = b'N'   # push None
  PERSID         = b'P'   # push persistent object; id is taken from string arg
  BINPERSID      = b'Q'   #  "       "         "  ;  "  "   "     "  stack
  REDUCE         = b'R'   # apply callable to argtuple, both on stack
  STRING         = b'S'   # push string; NL-terminated string argument
  BINSTRING      = b'T'   # push string; counted binary string argument
  SHORT_BINSTRING= b'U'   #  "     "   ;    "      "       "      " < 256 bytes
  UNICODE        = b'V'   # push Unicode string; raw-unicode-escaped'd argument
  BINUNICODE     = b'X'   #   "     "       "  ; counted UTF-8 string argument
  APPEND         = b'a'   # append stack top to list below it
  BUILD          = b'b'   # call __setstate__ or __dict__.update()
  GLOBAL         = b'c'   # push self.find_class(modname, name); 2 string args
  DICT           = b'd'   # build a dict from stack items
  EMPTY_DICT     = b'}'   # push empty dict
  APPENDS        = b'e'   # extend list on stack by topmost stack slice
  GET            = b'g'   # push item from memo on stack; index is string arg
  BINGET         = b'h'   #   "    "    "    "   "   "  ;   "    " 1-byte arg
  INST           = b'i'   # build & push class instance
  LONG_BINGET    = b'j'   # push item from memo on stack; index is 4-byte arg
  LIST           = b'l'   # build list from topmost stack items
  EMPTY_LIST     = b']'   # push empty list
  OBJ            = b'o'   # build & push class instance
  PUT            = b'p'   # store stack top in memo; index is string arg
  BINPUT         = b'q'   #   "     "    "   "   " ;   "    " 1-byte arg
  LONG_BINPUT    = b'r'   #   "     "    "   "   " ;   "    " 4-byte arg
  SETITEM        = b's'   # add key+value pair to dict
  TUPLE          = b't'   # build tuple from topmost stack items
  EMPTY_TUPLE    = b')'   # push empty tuple
  SETITEMS       = b'u'   # modify dict by adding topmost key+value pairs
  BINFLOAT       = b'G'   # push float; arg is 8-byte float encoding
  
  TRUE           = b'I01\n'  # not an opcode; see INT docs in pickletools.py
  FALSE          = b'I00\n'  # not an opcode; see INT docs in pickletools.py
  
  # Protocol 2
  
  PROTO          = b'\x80'  # identify pickle protocol
  NEWOBJ         = b'\x81'  # build object by applying cls.__new__ to argtuple
  EXT1           = b'\x82'  # push object from extension registry; 1-byte index
  EXT2           = b'\x83'  # ditto, but 2-byte index
  EXT4           = b'\x84'  # ditto, but 4-byte index
  TUPLE1         = b'\x85'  # build 1-tuple from stack top
  TUPLE2         = b'\x86'  # build 2-tuple from two topmost stack items
  TUPLE3         = b'\x87'  # build 3-tuple from three topmost stack items
  NEWTRUE        = b'\x88'  # push True
  NEWFALSE       = b'\x89'  # push False
  LONG1          = b'\x8a'  # push long from < 256 bytes
  LONG4          = b'\x8b'  # push really big long
  
  _tuplesize2code = [EMPTY_TUPLE, TUPLE1, TUPLE2, TUPLE3]
  
  # Protocol 3 (Python 3.x)
  
  BINBYTES       = b'B'   # push bytes; counted binary string argument
  SHORT_BINBYTES = b'C'   #  "     "   ;    "      "       "      " < 256 bytes
  
  # Protocol 4
  
  SHORT_BINUNICODE = b'\x8c'  # push short string; UTF-8 length < 256 bytes
  BINUNICODE8      = b'\x8d'  # push very long string
  BINBYTES8        = b'\x8e'  # push very long bytes string
  EMPTY_SET        = b'\x8f'  # push empty set on the stack
  ADDITEMS         = b'\x90'  # modify set by adding topmost stack items
  FROZENSET        = b'\x91'  # build frozenset from topmost stack items
  NEWOBJ_EX        = b'\x92'  # like NEWOBJ but work with keyword only arguments
  STACK_GLOBAL     = b'\x93'  # same as GLOBAL but using names on the stacks
  MEMOIZE          = b'\x94'  # store top of the stack in memo
  FRAME            = b'\x95'  # indicate the beginning of a new frame
  
  # Protocol 5
  
  BYTEARRAY8       = b'\x96'  # push bytearray
  NEXT_BUFFER      = b'\x97'  # push next out-of-band buffer
  READONLY_BUFFER  = b'\x98'  # make top of stack readonly
  
  __all__.extend([x for x in dir() if re.match("[A-Z][A-Z0-9_]+$", x)])
  
  
  class _Framer:
  
      _FRAME_SIZE_MIN = 4
      _FRAME_SIZE_TARGET = 64 * 1024
  
      def __init__(self, file_write):
          self.file_write = file_write
          self.current_frame = None
  
      def start_framing(self):
          self.current_frame = io.BytesIO()
  
      def end_framing(self):
          if self.current_frame and self.current_frame.tell() > 0:
              self.commit_frame(force=True)
              self.current_frame = None
  
      def commit_frame(self, force=False):
          if self.current_frame:
              f = self.current_frame
              if f.tell() >= self._FRAME_SIZE_TARGET or force:
                  data = f.getbuffer()
                  write = self.file_write
                  if len(data) >= self._FRAME_SIZE_MIN:
                      # Issue a single call to the write method of the underlying
                      # file object for the frame opcode with the size of the
                      # frame. The concatenation is expected to be less expensive
                      # than issuing an additional call to write.
                      write(FRAME + pack("<Q", len(data)))
  
                  # Issue a separate call to write to append the frame
                  # contents without concatenation to the above to avoid a
                  # memory copy.
                  write(data)
  
                  # Start the new frame with a new io.BytesIO instance so that
                  # the file object can have delayed access to the previous frame
                  # contents via an unreleased memoryview of the previous
                  # io.BytesIO instance.
                  self.current_frame = io.BytesIO()
  
      def write(self, data):
          if self.current_frame:
              return self.current_frame.write(data)
          else:
              return self.file_write(data)
  
      def write_large_bytes(self, header, payload):
          write = self.file_write
          if self.current_frame:
              # Terminate the current frame and flush it to the file.
              self.commit_frame(force=True)
  
          # Perform direct write of the header and payload of the large binary
          # object. Be careful not to concatenate the header and the payload
          # prior to calling 'write' as we do not want to allocate a large
          # temporary bytes object.
          # We intentionally do not insert a protocol 4 frame opcode to make
          # it possible to optimize file.read calls in the loader.
          write(header)
          write(payload)
  
  
  class _Unframer:
  
      def __init__(self, file_read, file_readline, file_tell=None):
          self.file_read = file_read
          self.file_readline = file_readline
          self.current_frame = None
  
      def readinto(self, buf):
          if self.current_frame:
              n = self.current_frame.readinto(buf)
              if n == 0 and len(buf) != 0:
                  self.current_frame = None
                  n = len(buf)
                  buf[:] = self.file_read(n)
                  return n
              if n < len(buf):
                  raise UnpicklingError(
                      "pickle exhausted before end of frame")
              return n
          else:
              n = len(buf)
              buf[:] = self.file_read(n)
              return n
  
      def read(self, n):
          if self.current_frame:
              data = self.current_frame.read(n)
              if not data and n != 0:
                  self.current_frame = None
                  return self.file_read(n)
              if len(data) < n:
                  raise UnpicklingError(
                      "pickle exhausted before end of frame")
              return data
          else:
              return self.file_read(n)
  
      def readline(self):
          if self.current_frame:
              data = self.current_frame.readline()
              if not data:
                  self.current_frame = None
                  return self.file_readline()
              if data[-1] != b'\n'[0]:
                  raise UnpicklingError(
                      "pickle exhausted before end of frame")
              return data
          else:
              return self.file_readline()
  
      def load_frame(self, frame_size):
          if self.current_frame and self.current_frame.read() != b'':
              raise UnpicklingError(
                  "beginning of a new frame before end of current frame")
          self.current_frame = io.BytesIO(self.file_read(frame_size))
  
  
  # Tools used for pickling.
  
  def _getattribute(obj, name):
      for subpath in name.split('.'):
          if subpath == '<locals>':
              raise AttributeError("Can't get local attribute {!r} on {!r}"
                                   .format(name, obj))
          try:
              parent = obj
              obj = getattr(obj, subpath)
          except AttributeError:
              raise AttributeError("Can't get attribute {!r} on {!r}"
                                   .format(name, obj)) from None
      return obj, parent
  
  def whichmodule(obj, name):
      """Find the module an object belong to."""
      module_name = getattr(obj, '__module__', None)
      if module_name is not None:
          return module_name
      # Protect the iteration by using a list copy of sys.modules against dynamic
      # modules that trigger imports of other modules upon calls to getattr.
      for module_name, module in list(sys.modules.items()):
          if module_name == '__main__' or module is None:
              continue
          try:
              if _getattribute(module, name)[0] is obj:
                  return module_name
          except AttributeError:
              pass
      return '__main__'
  
  def encode_long(x):
      r"""Encode a long to a two's complement little-endian binary string.
      Note that 0 is a special case, returning an empty string, to save a
      byte in the LONG1 pickling context.
  
      >>> encode_long(0)
      b''
      >>> encode_long(255)
      b'\xff\x00'
      >>> encode_long(32767)
      b'\xff\x7f'
      >>> encode_long(-256)
      b'\x00\xff'
      >>> encode_long(-32768)
      b'\x00\x80'
      >>> encode_long(-128)
      b'\x80'
      >>> encode_long(127)
      b'\x7f'
      >>>
      """
      if x == 0:
          return b''
      nbytes = (x.bit_length() >> 3) + 1
      result = x.to_bytes(nbytes, byteorder='little', signed=True)
      if x < 0 and nbytes > 1:
          if result[-1] == 0xff and (result[-2] & 0x80) != 0:
              result = result[:-1]
      return result
  
  def decode_long(data):
      r"""Decode a long from a two's complement little-endian binary string.
  
      >>> decode_long(b'')
      0
      >>> decode_long(b"\xff\x00")
      255
      >>> decode_long(b"\xff\x7f")
      32767
      >>> decode_long(b"\x00\xff")
      -256
      >>> decode_long(b"\x00\x80")
      -32768
      >>> decode_long(b"\x80")
      -128
      >>> decode_long(b"\x7f")
      127
      """
      return int.from_bytes(data, byteorder='little', signed=True)
  
  
  # Pickling machinery
  
  class _Pickler:
  
      def __init__(self, file, protocol=None, *, fix_imports=True,
                   buffer_callback=None):
          """This takes a binary file for writing a pickle data stream.
  
          The optional *protocol* argument tells the pickler to use the
          given protocol; supported protocols are 0, 1, 2, 3 and 4.  The
          default protocol is 4. It was introduced in Python 3.4, it is
          incompatible with previous versions.
  
          Specifying a negative protocol version selects the highest
          protocol version supported.  The higher the protocol used, the
          more recent the version of Python needed to read the pickle
          produced.
  
          The *file* argument must have a write() method that accepts a
          single bytes argument. It can thus be a file object opened for
          binary writing, an io.BytesIO instance, or any other custom
          object that meets this interface.
  
          If *fix_imports* is True and *protocol* is less than 3, pickle
          will try to map the new Python 3 names to the old module names
          used in Python 2, so that the pickle data stream is readable
          with Python 2.
  
          If *buffer_callback* is None (the default), buffer views are
          serialized into *file* as part of the pickle stream.
  
          If *buffer_callback* is not None, then it can be called any number
          of times with a buffer view.  If the callback returns a false value
          (such as None), the given buffer is out-of-band; otherwise the
          buffer is serialized in-band, i.e. inside the pickle stream.
  
          It is an error if *buffer_callback* is not None and *protocol*
          is None or smaller than 5.
          """
          if protocol is None:
              protocol = DEFAULT_PROTOCOL
          if protocol < 0:
              protocol = HIGHEST_PROTOCOL
          elif not 0 <= protocol <= HIGHEST_PROTOCOL:
              raise ValueError("pickle protocol must be <= %d" % HIGHEST_PROTOCOL)
          if buffer_callback is not None and protocol < 5:
              raise ValueError("buffer_callback needs protocol >= 5")
          self._buffer_callback = buffer_callback
          try:
              self._file_write = file.write
          except AttributeError:
              raise TypeError("file must have a 'write' attribute")
          self.framer = _Framer(self._file_write)
          self.write = self.framer.write
          self._write_large_bytes = self.framer.write_large_bytes
          self.memo = {}
          self.proto = int(protocol)
          self.bin = protocol >= 1
          self.fast = 0
          self.fix_imports = fix_imports and protocol < 3
          ## Stackless addition BEGIN
          try:
              from _stackless import _pickle_moduledict
          except ImportError:
              _pickle_moduledict = lambda self, obj:None
          self._pickle_moduledict = _pickle_moduledict
          ## Stackless addition END
  
      def clear_memo(self):
          """Clears the pickler's "memo".
  
          The memo is the data structure that remembers which objects the
          pickler has already seen, so that shared or recursive objects
          are pickled by reference and not by value.  This method is
          useful when re-using picklers.
          """
          self.memo.clear()
  
      def dump(self, obj):
          """Write a pickled representation of obj to the open file."""
          # Check whether Pickler was initialized correctly. This is
          # only needed to mimic the behavior of _pickle.Pickler.dump().
          if not hasattr(self, "_file_write"):
              raise PicklingError("Pickler.__init__() was not called by "
                                  "%s.__init__()" % (self.__class__.__name__,))
          if self.proto >= 2:
              self.write(PROTO + pack("<B", self.proto))
          if self.proto >= 4:
              self.framer.start_framing()
          self.save(obj)
          self.write(STOP)
          self.framer.end_framing()
  
      def memoize(self, obj):
          """Store an object in the memo."""
  
          # The Pickler memo is a dictionary mapping object ids to 2-tuples
          # that contain the Unpickler memo key and the object being memoized.
          # The memo key is written to the pickle and will become
          # the key in the Unpickler's memo.  The object is stored in the
          # Pickler memo so that transient objects are kept alive during
          # pickling.
  
          # The use of the Unpickler memo length as the memo key is just a
          # convention.  The only requirement is that the memo values be unique.
          # But there appears no advantage to any other scheme, and this
          # scheme allows the Unpickler memo to be implemented as a plain (but
          # growable) array, indexed by memo key.
          if self.fast:
              return
          assert id(obj) not in self.memo
          idx = len(self.memo)
          self.write(self.put(idx))
          self.memo[id(obj)] = idx, obj
  
      # Return a PUT (BINPUT, LONG_BINPUT) opcode string, with argument i.
      def put(self, idx):
          if self.proto >= 4:
              return MEMOIZE
          elif self.bin:
              if idx < 256:
                  return BINPUT + pack("<B", idx)
              else:
                  return LONG_BINPUT + pack("<I", idx)
          else:
              return PUT + repr(idx).encode("ascii") + b'\n'
  
      # Return a GET (BINGET, LONG_BINGET) opcode string, with argument i.
      def get(self, i):
          if self.bin:
              if i < 256:
                  return BINGET + pack("<B", i)
              else:
                  return LONG_BINGET + pack("<I", i)
  
          return GET + repr(i).encode("ascii") + b'\n'
  
      def save(self, obj, save_persistent_id=True):
          self.framer.commit_frame()
  
          # Check for persistent id (defined by a subclass)
          pid = self.persistent_id(obj)
          if pid is not None and save_persistent_id:
              self.save_pers(pid)
              return
  
          # Check the memo
          x = self.memo.get(id(obj))
          if x is not None:
              self.write(self.get(x[0]))
              return
  
          rv = NotImplemented
          reduce = getattr(self, "reducer_override", None)
          if reduce is not None:
              rv = reduce(obj)
  
          if rv is NotImplemented:
              # Check the type dispatch table
              t = type(obj)
              f = self.dispatch.get(t)
              if f is not None:
                  f(self, obj)  # Call unbound method with explicit self
                  return
  
              # Check private dispatch table if any, or else
              # copyreg.dispatch_table
              reduce = getattr(self, 'dispatch_table', dispatch_table).get(t)
              if reduce is not None:
                  rv = reduce(obj)
              else:
                  # Check for a class with a custom metaclass; treat as regular
                  # class
                  if issubclass(t, type):
                      self.save_global(obj)
                      return
  
                  # Check for a __reduce_ex__ method, fall back to __reduce__
                  reduce = getattr(obj, "__reduce_ex__", None)
                  if reduce is not None:
                      rv = reduce(self.proto)
                  else:
                      reduce = getattr(obj, "__reduce__", None)
                      if reduce is not None:
                          rv = reduce()
                      else:
                          raise PicklingError("Can't pickle %r object: %r" %
                                              (t.__name__, obj))
  
          # Check for string returned by reduce(), meaning "save as global"
          if isinstance(rv, str):
              self.save_global(obj, rv)
              return
  
          # Assert that reduce() returned a tuple
          if not isinstance(rv, tuple):
              raise PicklingError("%s must return string or tuple" % reduce)
  
          # Assert that it returned an appropriately sized tuple
          l = len(rv)
          if not (2 <= l <= 6):
              raise PicklingError("Tuple returned by %s must have "
                                  "two to six elements" % reduce)
  
          # Save the reduce() output and finally memoize the object
          self.save_reduce(obj=obj, *rv)
  
      def persistent_id(self, obj):
          # This exists so a subclass can override it
          return None
  
      def save_pers(self, pid):
          # Save a persistent id reference
          if self.bin:
              self.save(pid, save_persistent_id=False)
              self.write(BINPERSID)
          else:
              try:
                  self.write(PERSID + str(pid).encode("ascii") + b'\n')
              except UnicodeEncodeError:
                  raise PicklingError(
                      "persistent IDs in protocol 0 must be ASCII strings")
  
      def save_reduce(self, func, args, state=None, listitems=None,
                      dictitems=None, state_setter=None, obj=None):
          # This API is called by some subclasses
  
          if not isinstance(args, tuple):
              raise PicklingError("args from save_reduce() must be a tuple")
          if not callable(func):
              raise PicklingError("func from save_reduce() must be callable")
  
          save = self.save
          write = self.write
  
          func_name = getattr(func, "__name__", "")
          if self.proto >= 2 and func_name == "__newobj_ex__":
              cls, args, kwargs = args
              if not hasattr(cls, "__new__"):
                  raise PicklingError("args[0] from {} args has no __new__"
                                      .format(func_name))
              if obj is not None and cls is not obj.__class__:
                  raise PicklingError("args[0] from {} args has the wrong class"
                                      .format(func_name))
              if self.proto >= 4:
                  save(cls)
                  save(args)
                  save(kwargs)
                  write(NEWOBJ_EX)
              else:
                  func = partial(cls.__new__, cls, *args, **kwargs)
                  save(func)
                  save(())
                  write(REDUCE)
          elif self.proto >= 2 and func_name == "__newobj__":
              # A __reduce__ implementation can direct protocol 2 or newer to
              # use the more efficient NEWOBJ opcode, while still
              # allowing protocol 0 and 1 to work normally.  For this to
              # work, the function returned by __reduce__ should be
              # called __newobj__, and its first argument should be a
              # class.  The implementation for __newobj__
              # should be as follows, although pickle has no way to
              # verify this:
              #
              # def __newobj__(cls, *args):
              #     return cls.__new__(cls, *args)
              #
              # Protocols 0 and 1 will pickle a reference to __newobj__,
              # while protocol 2 (and above) will pickle a reference to
              # cls, the remaining args tuple, and the NEWOBJ code,
              # which calls cls.__new__(cls, *args) at unpickling time
              # (see load_newobj below).  If __reduce__ returns a
              # three-tuple, the state from the third tuple item will be
              # pickled regardless of the protocol, calling __setstate__
              # at unpickling time (see load_build below).
              #
              # Note that no standard __newobj__ implementation exists;
              # you have to provide your own.  This is to enforce
              # compatibility with Python 2.2 (pickles written using
              # protocol 0 or 1 in Python 2.3 should be unpicklable by
              # Python 2.2).
              cls = args[0]
              if not hasattr(cls, "__new__"):
                  raise PicklingError(
                      "args[0] from __newobj__ args has no __new__")
              if obj is not None and cls is not obj.__class__:
                  raise PicklingError(
                      "args[0] from __newobj__ args has the wrong class")
              args = args[1:]
              save(cls)
              save(args)
              write(NEWOBJ)
          else:
              save(func)
              save(args)
              write(REDUCE)
  
          if obj is not None:
              # If the object is already in the memo, this means it is
              # recursive. In this case, throw away everything we put on the
              # stack, and fetch the object back from the memo.
              if id(obj) in self.memo:
                  write(POP + self.get(self.memo[id(obj)][0]))
              else:
                  self.memoize(obj)
  
          # More new special cases (that work with older protocols as
          # well): when __reduce__ returns a tuple with 4 or 5 items,
          # the 4th and 5th item should be iterators that provide list
          # items and dict items (as (key, value) tuples), or None.
  
          if listitems is not None:
              self._batch_appends(listitems)
  
          if dictitems is not None:
              self._batch_setitems(dictitems)
  
          if state is not None:
              if state_setter is None:
                  save(state)
                  write(BUILD)
              else:
                  # If a state_setter is specified, call it instead of load_build
                  # to update obj's with its previous state.
                  # First, push state_setter and its tuple of expected arguments
                  # (obj, state) onto the stack.
                  save(state_setter)
                  save(obj)  # simple BINGET opcode as obj is already memoized.
                  save(state)
                  write(TUPLE2)
                  # Trigger a state_setter(obj, state) function call.
                  write(REDUCE)
                  # The purpose of state_setter is to carry-out an
                  # inplace modification of obj. We do not care about what the
                  # method might return, so its output is eventually removed from
                  # the stack.
                  write(POP)
  
      # Methods below this point are dispatched through the dispatch table
  
      dispatch = {}
  
      def save_none(self, obj):
          self.write(NONE)
      dispatch[type(None)] = save_none
  
      def save_bool(self, obj):
          if self.proto >= 2:
              self.write(NEWTRUE if obj else NEWFALSE)
          else:
              self.write(TRUE if obj else FALSE)
      dispatch[bool] = save_bool
  
      def save_long(self, obj):
          if self.bin:
              # If the int is small enough to fit in a signed 4-byte 2's-comp
              # format, we can store it more efficiently than the general
              # case.
              # First one- and two-byte unsigned ints:
              if obj >= 0:
                  if obj <= 0xff:
                      self.write(BININT1 + pack("<B", obj))
                      return
                  if obj <= 0xffff:
                      self.write(BININT2 + pack("<H", obj))
                      return
              # Next check for 4-byte signed ints:
              if -0x80000000 <= obj <= 0x7fffffff:
                  self.write(BININT + pack("<i", obj))
                  return
          if self.proto >= 2:
              encoded = encode_long(obj)
              n = len(encoded)
              if n < 256:
                  self.write(LONG1 + pack("<B", n) + encoded)
              else:
                  self.write(LONG4 + pack("<i", n) + encoded)
              return
          if -0x80000000 <= obj <= 0x7fffffff:
              self.write(INT + repr(obj).encode("ascii") + b'\n')
          else:
              self.write(LONG + repr(obj).encode("ascii") + b'L\n')
      dispatch[int] = save_long
  
      def save_float(self, obj):
          if self.bin:
              self.write(BINFLOAT + pack('>d', obj))
          else:
              self.write(FLOAT + repr(obj).encode("ascii") + b'\n')
      dispatch[float] = save_float
  
      def save_bytes(self, obj):
          if self.proto < 3:
              if not obj: # bytes object is empty
                  self.save_reduce(bytes, (), obj=obj)
              else:
                  self.save_reduce(codecs.encode,
                                   (str(obj, 'latin1'), 'latin1'), obj=obj)
              return
          n = len(obj)
          if n <= 0xff:
              self.write(SHORT_BINBYTES + pack("<B", n) + obj)
          elif n > 0xffffffff and self.proto >= 4:
              self._write_large_bytes(BINBYTES8 + pack("<Q", n), obj)
          elif n >= self.framer._FRAME_SIZE_TARGET:
              self._write_large_bytes(BINBYTES + pack("<I", n), obj)
          else:
              self.write(BINBYTES + pack("<I", n) + obj)
          self.memoize(obj)
      dispatch[bytes] = save_bytes
  
      def save_bytearray(self, obj):
          if self.proto < 5:
              if not obj:  # bytearray is empty
                  self.save_reduce(bytearray, (), obj=obj)
              else:
                  self.save_reduce(bytearray, (bytes(obj),), obj=obj)
              return
          n = len(obj)
          if n >= self.framer._FRAME_SIZE_TARGET:
              self._write_large_bytes(BYTEARRAY8 + pack("<Q", n), obj)
          else:
              self.write(BYTEARRAY8 + pack("<Q", n) + obj)
      dispatch[bytearray] = save_bytearray
  
      def save_picklebuffer(self, obj):
          if self.proto < 5:
              raise PicklingError("PickleBuffer can only pickled with "
                                  "protocol >= 5")
          with obj.raw() as m:
              if not m.contiguous:
                  raise PicklingError("PickleBuffer can not be pickled when "
                                      "pointing to a non-contiguous buffer")
              in_band = True
              if self._buffer_callback is not None:
                  in_band = bool(self._buffer_callback(obj))
              if in_band:
                  # Write data in-band
                  # XXX The C implementation avoids a copy here
                  if m.readonly:
                      self.save_bytes(m.tobytes())
                  else:
                      self.save_bytearray(m.tobytes())
              else:
                  # Write data out-of-band
                  self.write(NEXT_BUFFER)
                  if m.readonly:
                      self.write(READONLY_BUFFER)
  
      dispatch[PickleBuffer] = save_picklebuffer
  
      def save_str(self, obj):
          if self.bin:
              encoded = obj.encode('utf-8', 'surrogatepass')
              n = len(encoded)
              if n <= 0xff and self.proto >= 4:
                  self.write(SHORT_BINUNICODE + pack("<B", n) + encoded)
              elif n > 0xffffffff and self.proto >= 4:
                  self._write_large_bytes(BINUNICODE8 + pack("<Q", n), encoded)
              elif n >= self.framer._FRAME_SIZE_TARGET:
                  self._write_large_bytes(BINUNICODE + pack("<I", n), encoded)
              else:
                  self.write(BINUNICODE + pack("<I", n) + encoded)
          else:
              obj = obj.replace("\\", "\\u005c")
              obj = obj.replace("\0", "\\u0000")
              obj = obj.replace("\n", "\\u000a")
              obj = obj.replace("\r", "\\u000d")
              obj = obj.replace("\x1a", "\\u001a")  # EOF on DOS
              self.write(UNICODE + obj.encode('raw-unicode-escape') +
                         b'\n')
          self.memoize(obj)
      dispatch[str] = save_str
  
      def save_tuple(self, obj):
          if not obj: # tuple is empty
              if self.bin:
                  self.write(EMPTY_TUPLE)
              else:
                  self.write(MARK + TUPLE)
              return
  
          n = len(obj)
          save = self.save
          memo = self.memo
          if n <= 3 and self.proto >= 2:
              for element in obj:
                  save(element)
              # Subtle.  Same as in the big comment below.
              if id(obj) in memo:
                  get = self.get(memo[id(obj)][0])
                  self.write(POP * n + get)
              else:
                  self.write(_tuplesize2code[n])
                  self.memoize(obj)
              return
  
          # proto 0 or proto 1 and tuple isn't empty, or proto > 1 and tuple
          # has more than 3 elements.
          write = self.write
          write(MARK)
          for element in obj:
              save(element)
  
          if id(obj) in memo:
              # Subtle.  d was not in memo when we entered save_tuple(), so
              # the process of saving the tuple's elements must have saved
              # the tuple itself:  the tuple is recursive.  The proper action
              # now is to throw away everything we put on the stack, and
              # simply GET the tuple (it's already constructed).  This check
              # could have been done in the "for element" loop instead, but
              # recursive tuples are a rare thing.
              get = self.get(memo[id(obj)][0])
              if self.bin:
                  write(POP_MARK + get)
              else:   # proto 0 -- POP_MARK not available
                  write(POP * (n+1) + get)
              return
  
          # No recursion.
          write(TUPLE)
          self.memoize(obj)
  
      dispatch[tuple] = save_tuple
  
      def save_list(self, obj):
          if self.bin:
              self.write(EMPTY_LIST)
          else:   # proto 0 -- can't use EMPTY_LIST
              self.write(MARK + LIST)
  
          self.memoize(obj)
          self._batch_appends(obj)
  
      dispatch[list] = save_list
  
      _BATCHSIZE = 1000
  
      def _batch_appends(self, items):
          # Helper to batch up APPENDS sequences
          save = self.save
          write = self.write
  
          if not self.bin:
              for x in items:
                  save(x)
                  write(APPEND)
              return
  
          it = iter(items)
          while True:
              tmp = list(islice(it, self._BATCHSIZE))
              n = len(tmp)
              if n > 1:
                  write(MARK)
                  for x in tmp:
                      save(x)
                  write(APPENDS)
              elif n:
                  save(tmp[0])
                  write(APPEND)
              # else tmp is empty, and we're done
              if n < self._BATCHSIZE:
                  return
  
      def save_dict(self, obj):
          ## Stackless addition BEGIN
          modict_saver = self._pickle_moduledict(self, obj)
          if modict_saver is not None:
              return self.save_reduce(*modict_saver)
          ## Stackless addition END
          if self.bin:
              self.write(EMPTY_DICT)
          else:   # proto 0 -- can't use EMPTY_DICT
              self.write(MARK + DICT)
  
          self.memoize(obj)
          self._batch_setitems(obj.items())
  
      dispatch[dict] = save_dict
      if PyStringMap is not None:
          dispatch[PyStringMap] = save_dict
  
      def _batch_setitems(self, items):
          # Helper to batch up SETITEMS sequences; proto >= 1 only
          save = self.save
          write = self.write
  
          if not self.bin:
              for k, v in items:
                  save(k)
                  save(v)
                  write(SETITEM)
              return
  
          it = iter(items)
          while True:
              tmp = list(islice(it, self._BATCHSIZE))
              n = len(tmp)
              if n > 1:
                  write(MARK)
                  for k, v in tmp:
                      save(k)
                      save(v)
                  write(SETITEMS)
              elif n:
                  k, v = tmp[0]
                  save(k)
                  save(v)
                  write(SETITEM)
              # else tmp is empty, and we're done
              if n < self._BATCHSIZE:
                  return
  
      def save_set(self, obj):
          save = self.save
          write = self.write
  
          if self.proto < 4:
              self.save_reduce(set, (list(obj),), obj=obj)
              return
  
          write(EMPTY_SET)
          self.memoize(obj)
  
          it = iter(obj)
          while True:
              batch = list(islice(it, self._BATCHSIZE))
              n = len(batch)
              if n > 0:
                  write(MARK)
                  for item in batch:
                      save(item)
                  write(ADDITEMS)
              if n < self._BATCHSIZE:
                  return
      dispatch[set] = save_set
  
      def save_frozenset(self, obj):
          save = self.save
          write = self.write
  
          if self.proto < 4:
              self.save_reduce(frozenset, (list(obj),), obj=obj)
              return
  
          write(MARK)
          for item in obj:
              save(item)
  
          if id(obj) in self.memo:
              # If the object is already in the memo, this means it is
              # recursive. In this case, throw away everything we put on the
              # stack, and fetch the object back from the memo.
              write(POP_MARK + self.get(self.memo[id(obj)][0]))
              return
  
          write(FROZENSET)
          self.memoize(obj)
      dispatch[frozenset] = save_frozenset
  
      def save_global(self, obj, name=None):
          write = self.write
          memo = self.memo
  
          if name is None:
              name = getattr(obj, '__qualname__', None)
          if name is None:
              name = obj.__name__
  
          module_name = whichmodule(obj, name)
          try:
              __import__(module_name, level=0)
              module = sys.modules[module_name]
              obj2, parent = _getattribute(module, name)
          except (ImportError, KeyError, AttributeError):
              raise PicklingError(
                  "Can't pickle %r: it's not found as %s.%s" %
                  (obj, module_name, name)) from None
          else:
              if obj2 is not obj:
                  raise PicklingError(
                      "Can't pickle %r: it's not the same object as %s.%s" %
                      (obj, module_name, name))
  
          if self.proto >= 2:
              code = _extension_registry.get((module_name, name))
              if code:
                  assert code > 0
                  if code <= 0xff:
                      write(EXT1 + pack("<B", code))
                  elif code <= 0xffff:
                      write(EXT2 + pack("<H", code))
                  else:
                      write(EXT4 + pack("<i", code))
                  return
          lastname = name.rpartition('.')[2]
          if parent is module:
              name = lastname
          # Non-ASCII identifiers are supported only with protocols >= 3.
          if self.proto >= 4:
              self.save(module_name)
              self.save(name)
              write(STACK_GLOBAL)
          elif parent is not module:
              self.save_reduce(getattr, (parent, lastname))
          elif self.proto >= 3:
              write(GLOBAL + bytes(module_name, "utf-8") + b'\n' +
                    bytes(name, "utf-8") + b'\n')
          else:
              if self.fix_imports:
                  r_name_mapping = _compat_pickle.REVERSE_NAME_MAPPING
                  r_import_mapping = _compat_pickle.REVERSE_IMPORT_MAPPING
                  if (module_name, name) in r_name_mapping:
                      module_name, name = r_name_mapping[(module_name, name)]
                  elif module_name in r_import_mapping:
                      module_name = r_import_mapping[module_name]
              try:
                  write(GLOBAL + bytes(module_name, "ascii") + b'\n' +
                        bytes(name, "ascii") + b'\n')
              except UnicodeEncodeError:
                  raise PicklingError(
                      "can't pickle global identifier '%s.%s' using "
                      "pickle protocol %i" % (module, name, self.proto)) from None
  
          self.memoize(obj)
  
      def save_type(self, obj):
          if obj is type(None):
              return self.save_reduce(type, (None,), obj=obj)
          elif obj is type(NotImplemented):
              return self.save_reduce(type, (NotImplemented,), obj=obj)
          elif obj is type(...):
              return self.save_reduce(type, (...,), obj=obj)
          return self.save_global(obj)
  
      ## Stackless addition BEGIN
      def save_function(self, obj):
          try:
              return self.save_global(obj)
          except PicklingError as e:
              # Check copy_reg.dispatch_table
              reduce = dispatch_table.get(type(obj))
              if reduce:
                  rv = reduce(obj)
              else:
                  # Check for a __reduce_ex__ method, fall back to __reduce__
                  reduce = getattr(obj, "__reduce_ex__", None)
                  if reduce:
                      try:
                          rv = reduce(self.proto)
                      except PicklingError:
                          raise
                      except Exception as e2:
                          raise PicklingError("Can't reduce function %r" % (obj,)) from e2
                  else:
                      reduce = getattr(obj, "__reduce__", None)
                      if reduce:
                          try:
                              rv = reduce()
                          except PicklingError:
                              raise
                          except Exception as e2:
                              raise PicklingError("Can't reduce function %r" % (obj,)) from e2
                      else:
                          raise e
          return self.save_reduce(obj=obj, *rv)
  
      dispatch[FunctionType] = save_function
      ## Stackless addition END
      dispatch[type] = save_type
  
  
  # Unpickling machinery
  
  class _Unpickler:
  
      def __init__(self, file, *, fix_imports=True,
                   encoding="ASCII", errors="strict", buffers=None):
          """This takes a binary file for reading a pickle data stream.
  
          The protocol version of the pickle is detected automatically, so
          no proto argument is needed.
  
          The argument *file* must have two methods, a read() method that
          takes an integer argument, and a readline() method that requires
          no arguments.  Both methods should return bytes.  Thus *file*
          can be a binary file object opened for reading, an io.BytesIO
          object, or any other custom object that meets this interface.
  
          The file-like object must have two methods, a read() method
          that takes an integer argument, and a readline() method that
          requires no arguments.  Both methods should return bytes.
          Thus file-like object can be a binary file object opened for
          reading, a BytesIO object, or any other custom object that
          meets this interface.
  
          If *buffers* is not None, it should be an iterable of buffer-enabled
          objects that is consumed each time the pickle stream references
          an out-of-band buffer view.  Such buffers have been given in order
          to the *buffer_callback* of a Pickler object.
  
          If *buffers* is None (the default), then the buffers are taken
          from the pickle stream, assuming they are serialized there.
          It is an error for *buffers* to be None if the pickle stream
          was produced with a non-None *buffer_callback*.
  
          Other optional arguments are *fix_imports*, *encoding* and
          *errors*, which are used to control compatibility support for
          pickle stream generated by Python 2.  If *fix_imports* is True,
          pickle will try to map the old Python 2 names to the new names
          used in Python 3.  The *encoding* and *errors* tell pickle how
          to decode 8-bit string instances pickled by Python 2; these
          default to 'ASCII' and 'strict', respectively. *encoding* can be
          'bytes' to read theses 8-bit string instances as bytes objects.
          """
          self._buffers = iter(buffers) if buffers is not None else None
          self._file_readline = file.readline
          self._file_read = file.read
          self.memo = {}
          self.encoding = encoding
          self.errors = errors
          self.proto = 0
          self.fix_imports = fix_imports
  
      def load(self):
          """Read a pickled object representation from the open file.
  
          Return the reconstituted object hierarchy specified in the file.
          """
          # Check whether Unpickler was initialized correctly. This is
          # only needed to mimic the behavior of _pickle.Unpickler.dump().
          if not hasattr(self, "_file_read"):
              raise UnpicklingError("Unpickler.__init__() was not called by "
                                    "%s.__init__()" % (self.__class__.__name__,))
          self._unframer = _Unframer(self._file_read, self._file_readline)
          self.read = self._unframer.read
          self.readinto = self._unframer.readinto
          self.readline = self._unframer.readline
          self.metastack = []
          self.stack = []
          self.append = self.stack.append
          self.proto = 0
          read = self.read
          dispatch = self.dispatch
          try:
              while True:
                  key = read(1)
                  if not key:
                      raise EOFError
                  assert isinstance(key, bytes_types)
                  dispatch[key[0]](self)
          except _Stop as stopinst:
              return stopinst.value
  
      # Return a list of items pushed in the stack after last MARK instruction.
      def pop_mark(self):
          items = self.stack
          self.stack = self.metastack.pop()
          self.append = self.stack.append
          return items
  
      def persistent_load(self, pid):
          raise UnpicklingError("unsupported persistent id encountered")
  
      dispatch = {}
  
      def load_proto(self):
          proto = self.read(1)[0]
          if not 0 <= proto <= HIGHEST_PROTOCOL:
              raise ValueError("unsupported pickle protocol: %d" % proto)
          self.proto = proto
      dispatch[PROTO[0]] = load_proto
  
      def load_frame(self):
          frame_size, = unpack('<Q', self.read(8))
          if frame_size > sys.maxsize:
              raise ValueError("frame size > sys.maxsize: %d" % frame_size)
          self._unframer.load_frame(frame_size)
      dispatch[FRAME[0]] = load_frame
  
      def load_persid(self):
          try:
              pid = self.readline()[:-1].decode("ascii")
          except UnicodeDecodeError:
              raise UnpicklingError(
                  "persistent IDs in protocol 0 must be ASCII strings")
          self.append(self.persistent_load(pid))
      dispatch[PERSID[0]] = load_persid
  
      def load_binpersid(self):
          pid = self.stack.pop()
          self.append(self.persistent_load(pid))
      dispatch[BINPERSID[0]] = load_binpersid
  
      def load_none(self):
          self.append(None)
      dispatch[NONE[0]] = load_none
  
      def load_false(self):
          self.append(False)
      dispatch[NEWFALSE[0]] = load_false
  
      def load_true(self):
          self.append(True)
      dispatch[NEWTRUE[0]] = load_true
  
      def load_int(self):
          data = self.readline()
          if data == FALSE[1:]:
              val = False
          elif data == TRUE[1:]:
              val = True
          else:
              val = int(data, 0)
          self.append(val)
      dispatch[INT[0]] = load_int
  
      def load_binint(self):
          self.append(unpack('<i', self.read(4))[0])
      dispatch[BININT[0]] = load_binint
  
      def load_binint1(self):
          self.append(self.read(1)[0])
      dispatch[BININT1[0]] = load_binint1
  
      def load_binint2(self):
          self.append(unpack('<H', self.read(2))[0])
      dispatch[BININT2[0]] = load_binint2
  
      def load_long(self):
          val = self.readline()[:-1]
          if val and val[-1] == b'L'[0]:
              val = val[:-1]
          self.append(int(val, 0))
      dispatch[LONG[0]] = load_long
  
      def load_long1(self):
          n = self.read(1)[0]
          data = self.read(n)
          self.append(decode_long(data))
      dispatch[LONG1[0]] = load_long1
  
      def load_long4(self):
          n, = unpack('<i', self.read(4))
          if n < 0:
              # Corrupt or hostile pickle -- we never write one like this
              raise UnpicklingError("LONG pickle has negative byte count")
          data = self.read(n)
          self.append(decode_long(data))
      dispatch[LONG4[0]] = load_long4
  
      def load_float(self):
          self.append(float(self.readline()[:-1]))
      dispatch[FLOAT[0]] = load_float
  
      def load_binfloat(self):
          self.append(unpack('>d', self.read(8))[0])
      dispatch[BINFLOAT[0]] = load_binfloat
  
      def _decode_string(self, value):
          # Used to allow strings from Python 2 to be decoded either as
          # bytes or Unicode strings.  This should be used only with the
          # STRING, BINSTRING and SHORT_BINSTRING opcodes.
          if self.encoding == "bytes":
              return value
          else:
              return value.decode(self.encoding, self.errors)
  
      def load_string(self):
          data = self.readline()[:-1]
          # Strip outermost quotes
          if len(data) >= 2 and data[0] == data[-1] and data[0] in b'"\'':
              data = data[1:-1]
          else:
              raise UnpicklingError("the STRING opcode argument must be quoted")
          self.append(self._decode_string(codecs.escape_decode(data)[0]))
      dispatch[STRING[0]] = load_string
  
      def load_binstring(self):
          # Deprecated BINSTRING uses signed 32-bit length
          len, = unpack('<i', self.read(4))
          if len < 0:
              raise UnpicklingError("BINSTRING pickle has negative byte count")
          data = self.read(len)
          self.append(self._decode_string(data))
      dispatch[BINSTRING[0]] = load_binstring
  
      def load_binbytes(self):
          len, = unpack('<I', self.read(4))
          if len > maxsize:
              raise UnpicklingError("BINBYTES exceeds system's maximum size "
                                    "of %d bytes" % maxsize)
          self.append(self.read(len))
      dispatch[BINBYTES[0]] = load_binbytes
  
      def load_unicode(self):
          self.append(str(self.readline()[:-1], 'raw-unicode-escape'))
      dispatch[UNICODE[0]] = load_unicode
  
      def load_binunicode(self):
          len, = unpack('<I', self.read(4))
          if len > maxsize:
              raise UnpicklingError("BINUNICODE exceeds system's maximum size "
                                    "of %d bytes" % maxsize)
          self.append(str(self.read(len), 'utf-8', 'surrogatepass'))
      dispatch[BINUNICODE[0]] = load_binunicode
  
      def load_binunicode8(self):
          len, = unpack('<Q', self.read(8))
          if len > maxsize:
              raise UnpicklingError("BINUNICODE8 exceeds system's maximum size "
                                    "of %d bytes" % maxsize)
          self.append(str(self.read(len), 'utf-8', 'surrogatepass'))
      dispatch[BINUNICODE8[0]] = load_binunicode8
  
      def load_binbytes8(self):
          len, = unpack('<Q', self.read(8))
          if len > maxsize:
              raise UnpicklingError("BINBYTES8 exceeds system's maximum size "
                                    "of %d bytes" % maxsize)
          self.append(self.read(len))
      dispatch[BINBYTES8[0]] = load_binbytes8
  
      def load_bytearray8(self):
          len, = unpack('<Q', self.read(8))
          if len > maxsize:
              raise UnpicklingError("BYTEARRAY8 exceeds system's maximum size "
                                    "of %d bytes" % maxsize)
          b = bytearray(len)
          self.readinto(b)
          self.append(b)
      dispatch[BYTEARRAY8[0]] = load_bytearray8
  
      def load_next_buffer(self):
          if self._buffers is None:
              raise UnpicklingError("pickle stream refers to out-of-band data "
                                    "but no *buffers* argument was given")
          try:
              buf = next(self._buffers)
          except StopIteration:
              raise UnpicklingError("not enough out-of-band buffers")
          self.append(buf)
      dispatch[NEXT_BUFFER[0]] = load_next_buffer
  
      def load_readonly_buffer(self):
          buf = self.stack[-1]
          with memoryview(buf) as m:
              if not m.readonly:
                  self.stack[-1] = m.toreadonly()
      dispatch[READONLY_BUFFER[0]] = load_readonly_buffer
  
      def load_short_binstring(self):
          len = self.read(1)[0]
          data = self.read(len)
          self.append(self._decode_string(data))
      dispatch[SHORT_BINSTRING[0]] = load_short_binstring
  
      def load_short_binbytes(self):
          len = self.read(1)[0]
          self.append(self.read(len))
      dispatch[SHORT_BINBYTES[0]] = load_short_binbytes
  
      def load_short_binunicode(self):
          len = self.read(1)[0]
          self.append(str(self.read(len), 'utf-8', 'surrogatepass'))
      dispatch[SHORT_BINUNICODE[0]] = load_short_binunicode
  
      def load_tuple(self):
          items = self.pop_mark()
          self.append(tuple(items))
      dispatch[TUPLE[0]] = load_tuple
  
      def load_empty_tuple(self):
          self.append(())
      dispatch[EMPTY_TUPLE[0]] = load_empty_tuple
  
      def load_tuple1(self):
          self.stack[-1] = (self.stack[-1],)
      dispatch[TUPLE1[0]] = load_tuple1
  
      def load_tuple2(self):
          self.stack[-2:] = [(self.stack[-2], self.stack[-1])]
      dispatch[TUPLE2[0]] = load_tuple2
  
      def load_tuple3(self):
          self.stack[-3:] = [(self.stack[-3], self.stack[-2], self.stack[-1])]
      dispatch[TUPLE3[0]] = load_tuple3
  
      def load_empty_list(self):
          self.append([])
      dispatch[EMPTY_LIST[0]] = load_empty_list
  
      def load_empty_dictionary(self):
          self.append({})
      dispatch[EMPTY_DICT[0]] = load_empty_dictionary
  
      def load_empty_set(self):
          self.append(set())
      dispatch[EMPTY_SET[0]] = load_empty_set
  
      def load_frozenset(self):
          items = self.pop_mark()
          self.append(frozenset(items))
      dispatch[FROZENSET[0]] = load_frozenset
  
      def load_list(self):
          items = self.pop_mark()
          self.append(items)
      dispatch[LIST[0]] = load_list
  
      def load_dict(self):
          items = self.pop_mark()
          d = {items[i]: items[i+1]
               for i in range(0, len(items), 2)}
          self.append(d)
      dispatch[DICT[0]] = load_dict
  
      # INST and OBJ differ only in how they get a class object.  It's not
      # only sensible to do the rest in a common routine, the two routines
      # previously diverged and grew different bugs.
      # klass is the class to instantiate, and k points to the topmost mark
      # object, following which are the arguments for klass.__init__.
      def _instantiate(self, klass, args):
          if (args or not isinstance(klass, type) or
              hasattr(klass, "__getinitargs__")):
              try:
                  value = klass(*args)
              except TypeError as err:
                  raise TypeError("in constructor for %s: %s" %
                                  (klass.__name__, str(err)), sys.exc_info()[2])
          else:
              value = klass.__new__(klass)
          self.append(value)
  
      def load_inst(self):
          module = self.readline()[:-1].decode("ascii")
          name = self.readline()[:-1].decode("ascii")
          klass = self.find_class(module, name)
          self._instantiate(klass, self.pop_mark())
      dispatch[INST[0]] = load_inst
  
      def load_obj(self):
          # Stack is ... markobject classobject arg1 arg2 ...
          args = self.pop_mark()
          cls = args.pop(0)
          self._instantiate(cls, args)
      dispatch[OBJ[0]] = load_obj
  
      def load_newobj(self):
          args = self.stack.pop()
          cls = self.stack.pop()
          obj = cls.__new__(cls, *args)
          self.append(obj)
      dispatch[NEWOBJ[0]] = load_newobj
  
      def load_newobj_ex(self):
          kwargs = self.stack.pop()
          args = self.stack.pop()
          cls = self.stack.pop()
          obj = cls.__new__(cls, *args, **kwargs)
          self.append(obj)
      dispatch[NEWOBJ_EX[0]] = load_newobj_ex
  
      def load_global(self):
          module = self.readline()[:-1].decode("utf-8")
          name = self.readline()[:-1].decode("utf-8")
          klass = self.find_class(module, name)
          self.append(klass)
      dispatch[GLOBAL[0]] = load_global
  
      def load_stack_global(self):
          name = self.stack.pop()
          module = self.stack.pop()
          if type(name) is not str or type(module) is not str:
              raise UnpicklingError("STACK_GLOBAL requires str")
          self.append(self.find_class(module, name))
      dispatch[STACK_GLOBAL[0]] = load_stack_global
  
      def load_ext1(self):
          code = self.read(1)[0]
          self.get_extension(code)
      dispatch[EXT1[0]] = load_ext1
  
      def load_ext2(self):
          code, = unpack('<H', self.read(2))
          self.get_extension(code)
      dispatch[EXT2[0]] = load_ext2
  
      def load_ext4(self):
          code, = unpack('<i', self.read(4))
          self.get_extension(code)
      dispatch[EXT4[0]] = load_ext4
  
      def get_extension(self, code):
          nil = []
          obj = _extension_cache.get(code, nil)
          if obj is not nil:
              self.append(obj)
              return
          key = _inverted_registry.get(code)
          if not key:
              if code <= 0: # note that 0 is forbidden
                  # Corrupt or hostile pickle.
                  raise UnpicklingError("EXT specifies code <= 0")
              raise ValueError("unregistered extension code %d" % code)
          obj = self.find_class(*key)
          _extension_cache[code] = obj
          self.append(obj)
  
      def find_class(self, module, name):
          # Subclasses may override this.
          sys.audit('pickle.find_class', module, name)
          if self.proto < 3 and self.fix_imports:
              if (module, name) in _compat_pickle.NAME_MAPPING:
                  module, name = _compat_pickle.NAME_MAPPING[(module, name)]
              elif module in _compat_pickle.IMPORT_MAPPING:
                  module = _compat_pickle.IMPORT_MAPPING[module]
          __import__(module, level=0)
          if self.proto >= 4:
              return _getattribute(sys.modules[module], name)[0]
          else:
              return getattr(sys.modules[module], name)
  
      def load_reduce(self):
          stack = self.stack
          args = stack.pop()
          func = stack[-1]
          stack[-1] = func(*args)
      dispatch[REDUCE[0]] = load_reduce
  
      def load_pop(self):
          if self.stack:
              del self.stack[-1]
          else:
              self.pop_mark()
      dispatch[POP[0]] = load_pop
  
      def load_pop_mark(self):
          self.pop_mark()
      dispatch[POP_MARK[0]] = load_pop_mark
  
      def load_dup(self):
          self.append(self.stack[-1])
      dispatch[DUP[0]] = load_dup
  
      def load_get(self):
          i = int(self.readline()[:-1])
          self.append(self.memo[i])
      dispatch[GET[0]] = load_get
  
      def load_binget(self):
          i = self.read(1)[0]
          self.append(self.memo[i])
      dispatch[BINGET[0]] = load_binget
  
      def load_long_binget(self):
          i, = unpack('<I', self.read(4))
          self.append(self.memo[i])
      dispatch[LONG_BINGET[0]] = load_long_binget
  
      def load_put(self):
          i = int(self.readline()[:-1])
          if i < 0:
              raise ValueError("negative PUT argument")
          self.memo[i] = self.stack[-1]
      dispatch[PUT[0]] = load_put
  
      def load_binput(self):
          i = self.read(1)[0]
          if i < 0:
              raise ValueError("negative BINPUT argument")
          self.memo[i] = self.stack[-1]
      dispatch[BINPUT[0]] = load_binput
  
      def load_long_binput(self):
          i, = unpack('<I', self.read(4))
          if i > maxsize:
              raise ValueError("negative LONG_BINPUT argument")
          self.memo[i] = self.stack[-1]
      dispatch[LONG_BINPUT[0]] = load_long_binput
  
      def load_memoize(self):
          memo = self.memo
          memo[len(memo)] = self.stack[-1]
      dispatch[MEMOIZE[0]] = load_memoize
  
      def load_append(self):
          stack = self.stack
          value = stack.pop()
          list = stack[-1]
          list.append(value)
      dispatch[APPEND[0]] = load_append
  
      def load_appends(self):
          items = self.pop_mark()
          list_obj = self.stack[-1]
          try:
              extend = list_obj.extend
          except AttributeError:
              pass
          else:
              extend(items)
              return
          # Even if the PEP 307 requires extend() and append() methods,
          # fall back on append() if the object has no extend() method
          # for backward compatibility.
          append = list_obj.append
          for item in items:
              append(item)
      dispatch[APPENDS[0]] = load_appends
  
      def load_setitem(self):
          stack = self.stack
          value = stack.pop()
          key = stack.pop()
          dict = stack[-1]
          dict[key] = value
      dispatch[SETITEM[0]] = load_setitem
  
      def load_setitems(self):
          items = self.pop_mark()
          dict = self.stack[-1]
          for i in range(0, len(items), 2):
              dict[items[i]] = items[i + 1]
      dispatch[SETITEMS[0]] = load_setitems
  
      def load_additems(self):
          items = self.pop_mark()
          set_obj = self.stack[-1]
          if isinstance(set_obj, set):
              set_obj.update(items)
          else:
              add = set_obj.add
              for item in items:
                  add(item)
      dispatch[ADDITEMS[0]] = load_additems
  
      def load_build(self):
          stack = self.stack
          state = stack.pop()
          inst = stack[-1]
          setstate = getattr(inst, "__setstate__", None)
          if setstate is not None:
              setstate(state)
              return
          slotstate = None
          if isinstance(state, tuple) and len(state) == 2:
              state, slotstate = state
          if state:
              inst_dict = inst.__dict__
              intern = sys.intern
              for k, v in state.items():
                  if type(k) is str:
                      inst_dict[intern(k)] = v
                  else:
                      inst_dict[k] = v
          if slotstate:
              for k, v in slotstate.items():
                  setattr(inst, k, v)
      dispatch[BUILD[0]] = load_build
  
      def load_mark(self):
          self.metastack.append(self.stack)
          self.stack = []
          self.append = self.stack.append
      dispatch[MARK[0]] = load_mark
  
      def load_stop(self):
          value = self.stack.pop()
          raise _Stop(value)
      dispatch[STOP[0]] = load_stop
  
  
  # Shorthands
  
  def _dump(obj, file, protocol=None, *, fix_imports=True, buffer_callback=None):
      _Pickler(file, protocol, fix_imports=fix_imports,
               buffer_callback=buffer_callback).dump(obj)
  
  def _dumps(obj, protocol=None, *, fix_imports=True, buffer_callback=None):
      f = io.BytesIO()
      _Pickler(f, protocol, fix_imports=fix_imports,
               buffer_callback=buffer_callback).dump(obj)
      res = f.getvalue()
      assert isinstance(res, bytes_types)
      return res
  
  def _load(file, *, fix_imports=True, encoding="ASCII", errors="strict",
            buffers=None):
      return _Unpickler(file, fix_imports=fix_imports, buffers=buffers,
                       encoding=encoding, errors=errors).load()
  
  def _loads(s, *, fix_imports=True, encoding="ASCII", errors="strict",
             buffers=None):
      if isinstance(s, str):
          raise TypeError("Can't load pickle from unicode string")
      file = io.BytesIO(s)
      return _Unpickler(file, fix_imports=fix_imports, buffers=buffers,
                        encoding=encoding, errors=errors).load()
  
  # Use the faster _pickle if possible
  try:
      from _pickle import (
          PickleError,
          PicklingError,
          UnpicklingError,
          Pickler,
          Unpickler,
          dump,
          dumps,
          load,
          loads
      )
  except ImportError:
      Pickler, Unpickler = _Pickler, _Unpickler
      dump, dumps, load, loads = _dump, _dumps, _load, _loads
  
  # Doctest
  def _test():
      import doctest
      return doctest.testmod()
  
  if __name__ == "__main__":
      import argparse
      parser = argparse.ArgumentParser(
          description='display contents of the pickle files')
      parser.add_argument(
          'pickle_file', type=argparse.FileType('br'),
          nargs='*', help='the pickle file')
      parser.add_argument(
          '-t', '--test', action='store_true',
          help='run self-test suite')
      parser.add_argument(
          '-v', action='store_true',
          help='run verbosely; only affects self-test run')
      args = parser.parse_args()
      if args.test:
          _test()
      else:
          if not args.pickle_file:
              parser.print_help()
          else:
              import pprint
              for f in args.pickle_file:
                  obj = load(f)
                  pprint.pprint(obj)
  