text: """ codecs -- Python Codec Registry, API and helpers.
  
  
  Written by Marc-Andre Lemburg (mal@lemburg.com).
  
  (c) Copyright CNRI, All Rights Reserved. NO WARRANTY.
  
  """#"
  
  import builtins, sys
  
  ### Registry and builtin stateless codec functions
  
  try:
      from _codecs import *
  except ImportError as why:
      raise SystemError('Failed to load the builtin codecs: %s' % why)
  
  __all__ = ["register", "lookup", "open", "EncodedFile", "BOM", "BOM_BE",
             "BOM_LE", "BOM32_BE", "BOM32_LE", "BOM64_BE", "BOM64_LE",
             "BOM_UTF8", "BOM_UTF16", "BOM_UTF16_LE", "BOM_UTF16_BE",
             "BOM_UTF32", "BOM_UTF32_LE", "BOM_UTF32_BE",
             "strict_errors", "ignore_errors", "replace_errors",
             "xmlcharrefreplace_errors",
             "register_error", "lookup_error"]
  
  ### Constants
  
  #
  # Byte Order Mark (BOM = ZERO WIDTH NO-BREAK SPACE = U+FEFF)
  # and its possible byte string values
  # for UTF8/UTF16/UTF32 output and little/big endian machines
  #
  
  # UTF-8
  BOM_UTF8 = b'\xef\xbb\xbf'
  
  # UTF-16, little endian
  BOM_LE = BOM_UTF16_LE = b'\xff\xfe'
  
  # UTF-16, big endian
  BOM_BE = BOM_UTF16_BE = b'\xfe\xff'
  
  # UTF-32, little endian
  BOM_UTF32_LE = b'\xff\xfe\x00\x00'
  
  # UTF-32, big endian
  BOM_UTF32_BE = b'\x00\x00\xfe\xff'
  
  if sys.byteorder == 'little':
  
      # UTF-16, native endianness
      BOM = BOM_UTF16 = BOM_UTF16_LE
  
      # UTF-32, native endianness
      BOM_UTF32 = BOM_UTF32_LE
  
  else:
  
      # UTF-16, native endianness
      BOM = BOM_UTF16 = BOM_UTF16_BE
  
      # UTF-32, native endianness
      BOM_UTF32 = BOM_UTF32_BE
  
  # Old broken names (don't use in new code)
  BOM32_LE = BOM_UTF16_LE
  BOM32_BE = BOM_UTF16_BE
  BOM64_LE = BOM_UTF32_LE
  BOM64_BE = BOM_UTF32_BE
  
  
  ### Codec base classes (defining the API)
  
  class CodecInfo(tuple):
      """Codec details when looking up the codec registry"""
  
      # Private API to allow Python 3.4 to blacklist the known non-Unicode
      # codecs in the standard library. A more general mechanism to
      # reliably distinguish test encodings from other codecs will hopefully
      # be defined for Python 3.5
      #
      # See http://bugs.python.org/issue19619
      _is_text_encoding = True # Assume codecs are text encodings by default
  
      def __new__(cls, encode, decode, streamreader=None, streamwriter=None,
          incrementalencoder=None, incrementaldecoder=None, name=None,
          *, _is_text_encoding=None):
          self = tuple.__new__(cls, (encode, decode, streamreader, streamwriter))
          self.name = name
          self.encode = encode
          self.decode = decode
          self.incrementalencoder = incrementalencoder
          self.incrementaldecoder = incrementaldecoder
          self.streamwriter = streamwriter
          self.streamreader = streamreader
          if _is_text_encoding is not None:
              self._is_text_encoding = _is_text_encoding
          return self
  
      def __repr__(self):
          return "<%s.%s object for encoding %s at %#x>" % \
                  (self.__class__.__module__, self.__class__.__qualname__,
                   self.name, id(self))
  
  class Codec:
  
      """ Defines the interface for stateless encoders/decoders.
  
          The .encode()/.decode() methods may use different error
          handling schemes by providing the errors argument. These
          string values are predefined:
  
           'strict' - raise a ValueError error (or a subclass)
           'ignore' - ignore the character and continue with the next
           'replace' - replace with a suitable replacement character;
                      Python will use the official U+FFFD REPLACEMENT
                      CHARACTER for the builtin Unicode codecs on
                      decoding and '?' on encoding.
           'surrogateescape' - replace with private codepoints U+DCnn.
           'xmlcharrefreplace' - Replace with the appropriate XML
                                 character reference (only for encoding).
           'backslashreplace'  - Replace with backslashed escape sequences
                                 (only for encoding).
  
          The set of allowed values can be extended via register_error.
  
      """
      def encode(self, input, errors='strict'):
  
          """ Encodes the object input and returns a tuple (output
              object, length consumed).
  
              errors defines the error handling to apply. It defaults to
              'strict' handling.
  
              The method may not store state in the Codec instance. Use
              StreamCodec for codecs which have to keep state in order to
              make encoding/decoding efficient.
  
              The encoder must be able to handle zero length input and
              return an empty object of the output object type in this
              situation.
  
          """
          raise NotImplementedError
  
      def decode(self, input, errors='strict'):
  
          """ Decodes the object input and returns a tuple (output
              object, length consumed).
  
              input must be an object which provides the bf_getreadbuf
              buffer slot. Python strings, buffer objects and memory
              mapped files are examples of objects providing this slot.
  
              errors defines the error handling to apply. It defaults to
              'strict' handling.
  
              The method may not store state in the Codec instance. Use
              StreamCodec for codecs which have to keep state in order to
              make encoding/decoding efficient.
  
              The decoder must be able to handle zero length input and
              return an empty object of the output object type in this
              situation.
  
          """
          raise NotImplementedError
  
  class IncrementalEncoder(object):
      """
      An IncrementalEncoder encodes an input in multiple steps. The input can
      be passed piece by piece to the encode() method. The IncrementalEncoder
      remembers the state of the encoding process between calls to encode().
      """
      def __init__(self, errors='strict'):
          """
          Creates an IncrementalEncoder instance.
  
          The IncrementalEncoder may use different error handling schemes by
          providing the errors keyword argument. See the module docstring
          for a list of possible values.
          """
          self.errors = errors
          self.buffer = ""
  
      def encode(self, input, final=False):
          """
          Encodes input and returns the resulting object.
          """
          raise NotImplementedError
  
      def reset(self):
          """
          Resets the encoder to the initial state.
          """
  
      def getstate(self):
          """
          Return the current state of the encoder.
          """
          return 0
  
      def setstate(self, state):
          """
          Set the current state of the encoder. state must have been
          returned by getstate().
          """
  
  class BufferedIncrementalEncoder(IncrementalEncoder):
      """
      This subclass of IncrementalEncoder can be used as the baseclass for an
      incremental encoder if the encoder must keep some of the output in a
      buffer between calls to encode().
      """
      def __init__(self, errors='strict'):
          IncrementalEncoder.__init__(self, errors)
          # unencoded input that is kept between calls to encode()
          self.buffer = ""
  
      def _buffer_encode(self, input, errors, final):
          # Overwrite this method in subclasses: It must encode input
          # and return an (output, length consumed) tuple
          raise NotImplementedError
  
      def encode(self, input, final=False):
          # encode input (taking the buffer into account)
          data = self.buffer + input
          (result, consumed) = self._buffer_encode(data, self.errors, final)
          # keep unencoded input until the next call
          self.buffer = data[consumed:]
          return result
  
      def reset(self):
          IncrementalEncoder.reset(self)
          self.buffer = ""
  
      def getstate(self):
          return self.buffer or 0
  
      def setstate(self, state):
          self.buffer = state or ""
  
  class IncrementalDecoder(object):
      """
      An IncrementalDecoder decodes an input in multiple steps. The input can
      be passed piece by piece to the decode() method. The IncrementalDecoder
      remembers the state of the decoding process between calls to decode().
      """
      def __init__(self, errors='strict'):
          """
          Create a IncrementalDecoder instance.
  
          The IncrementalDecoder may use different error handling schemes by
          providing the errors keyword argument. See the module docstring
          for a list of possible values.
          """
          self.errors = errors
  
      def decode(self, input, final=False):
          """
          Decode input and returns the resulting object.
          """
          raise NotImplementedError
  
      def reset(self):
          """
          Reset the decoder to the initial state.
          """
  
      def getstate(self):
          """
          Return the current state of the decoder.
  
          This must be a (buffered_input, additional_state_info) tuple.
          buffered_input must be a bytes object containing bytes that
          were passed to decode() that have not yet been converted.
          additional_state_info must be a non-negative integer
          representing the state of the decoder WITHOUT yet having
          processed the contents of buffered_input.  In the initial state
          and after reset(), getstate() must return (b"", 0).
          """
          return (b"", 0)
  
      def setstate(self, state):
          """
          Set the current state of the decoder.
  
          state must have been returned by getstate().  The effect of
          setstate((b"", 0)) must be equivalent to reset().
          """
  
  class BufferedIncrementalDecoder(IncrementalDecoder):
      """
      This subclass of IncrementalDecoder can be used as the baseclass for an
      incremental decoder if the decoder must be able to handle incomplete
      byte sequences.
      """
      def __init__(self, errors='strict'):
          IncrementalDecoder.__init__(self, errors)
          # undecoded input that is kept between calls to decode()
          self.buffer = b""
  
      def _buffer_decode(self, input, errors, final):
          # Overwrite this method in subclasses: It must decode input
          # and return an (output, length consumed) tuple
          raise NotImplementedError
  
      def decode(self, input, final=False):
          # decode input (taking the buffer into account)
          data = self.buffer + input
          (result, consumed) = self._buffer_decode(data, self.errors, final)
          # keep undecoded input until the next call
          self.buffer = data[consumed:]
          return result
  
      def reset(self):
          IncrementalDecoder.reset(self)
          self.buffer = b""
  
      def getstate(self):
          # additional state info is always 0
          return (self.buffer, 0)
  
      def setstate(self, state):
          # ignore additional state info
          self.buffer = state[0]
  
  #
  # The StreamWriter and StreamReader class provide generic working
  # interfaces which can be used to implement new encoding submodules
  # very easily. See encodings/utf_8.py for an example on how this is
  # done.
  #
  
  class StreamWriter(Codec):
  
      def __init__(self, stream, errors='strict'):
  
          """ Creates a StreamWriter instance.
  
              stream must be a file-like object open for writing
              (binary) data.
  
              The StreamWriter may use different error handling
              schemes by providing the errors keyword argument. These
              parameters are predefined:
  
               'strict' - raise a ValueError (or a subclass)
               'ignore' - ignore the character and continue with the next
               'replace'- replace with a suitable replacement character
               'xmlcharrefreplace' - Replace with the appropriate XML
                                     character reference.
               'backslashreplace'  - Replace with backslashed escape
                                     sequences (only for encoding).
  
              The set of allowed parameter values can be extended via
              register_error.
          """
          self.stream = stream
          self.errors = errors
  
      def write(self, object):
  
          """ Writes the object's contents encoded to self.stream.
          """
          data, consumed = self.encode(object, self.errors)
          self.stream.write(data)
  
      def writelines(self, list):
  
          """ Writes the concatenated list of strings to the stream
              using .write().
          """
          self.write(''.join(list))
  
      def reset(self):
  
          """ Flushes and resets the codec buffers used for keeping state.
  
              Calling this method should ensure that the data on the
              output is put into a clean state, that allows appending
              of new fresh data without having to rescan the whole
              stream to recover state.
  
          """
          pass
  
      def seek(self, offset, whence=0):
          self.stream.seek(offset, whence)
          if whence == 0 and offset == 0:
              self.reset()
  
      def __getattr__(self, name,
                      getattr=getattr):
  
          """ Inherit all other methods from the underlying stream.
          """
          return getattr(self.stream, name)
  
      def __enter__(self):
          return self
  
      def __exit__(self, type, value, tb):
          self.stream.close()
  
  ###
  
  class StreamReader(Codec):
  
      charbuffertype = str
  
      def __init__(self, stream, errors='strict'):
  
          """ Creates a StreamReader instance.
  
              stream must be a file-like object open for reading
              (binary) data.
  
              The StreamReader may use different error handling
              schemes by providing the errors keyword argument. These
              parameters are predefined:
  
               'strict' - raise a ValueError (or a subclass)
               'ignore' - ignore the character and continue with the next
               'replace'- replace with a suitable replacement character;
  
              The set of allowed parameter values can be extended via
              register_error.
          """
          self.stream = stream
          self.errors = errors
          self.bytebuffer = b""
          self._empty_charbuffer = self.charbuffertype()
          self.charbuffer = self._empty_charbuffer
          self.linebuffer = None
  
      def decode(self, input, errors='strict'):
          raise NotImplementedError
  
      def read(self, size=-1, chars=-1, firstline=False):
  
          """ Decodes data from the stream self.stream and returns the
              resulting object.
  
              chars indicates the number of characters to read from the
              stream. read() will never return more than chars
              characters, but it might return less, if there are not enough
              characters available.
  
              size indicates the approximate maximum number of bytes to
              read from the stream for decoding purposes. The decoder
              can modify this setting as appropriate. The default value
              -1 indicates to read and decode as much as possible.  size
              is intended to prevent having to decode huge files in one
              step.
  
              If firstline is true, and a UnicodeDecodeError happens
              after the first line terminator in the input only the first line
              will be returned, the rest of the input will be kept until the
              next call to read().
  
              The method should use a greedy read strategy meaning that
              it should read as much data as is allowed within the
              definition of the encoding and the given size, e.g.  if
              optional encoding endings or state markers are available
              on the stream, these should be read too.
          """
          # If we have lines cached, first merge them back into characters
          if self.linebuffer:
              self.charbuffer = self._empty_charbuffer.join(self.linebuffer)
              self.linebuffer = None
  
          # read until we get the required number of characters (if available)
          while True:
              # can the request be satisfied from the character buffer?
              if chars >= 0:
                  if len(self.charbuffer) >= chars:
                      break
              elif size >= 0:
                  if len(self.charbuffer) >= size:
                      break
              # we need more data
              if size < 0:
                  newdata = self.stream.read()
              else:
                  newdata = self.stream.read(size)
              # decode bytes (those remaining from the last call included)
              data = self.bytebuffer + newdata
              if not data:
                  break
              try:
                  newchars, decodedbytes = self.decode(data, self.errors)
              except UnicodeDecodeError as exc:
                  if firstline:
                      newchars, decodedbytes = \
                          self.decode(data[:exc.start], self.errors)
                      lines = newchars.splitlines(keepends=True)
                      if len(lines)<=1:
                          raise
                  else:
                      raise
              # keep undecoded bytes until the next call
              self.bytebuffer = data[decodedbytes:]
              # put new characters in the character buffer
              self.charbuffer += newchars
              # there was no data available
              if not newdata:
                  break
          if chars < 0:
              # Return everything we've got
              result = self.charbuffer
              self.charbuffer = self._empty_charbuffer
          else:
              # Return the first chars characters
              result = self.charbuffer[:chars]
              self.charbuffer = self.charbuffer[chars:]
          return result
  
      def readline(self, size=None, keepends=True):
  
          """ Read one line from the input stream and return the
              decoded data.
  
              size, if given, is passed as size argument to the
              read() method.
  
          """
          # If we have lines cached from an earlier read, return
          # them unconditionally
          if self.linebuffer:
              line = self.linebuffer[0]
              del self.linebuffer[0]
              if len(self.linebuffer) == 1:
                  # revert to charbuffer mode; we might need more data
                  # next time
                  self.charbuffer = self.linebuffer[0]
                  self.linebuffer = None
              if not keepends:
                  line = line.splitlines(keepends=False)[0]
              return line
  
          readsize = size or 72
          line = self._empty_charbuffer
          # If size is given, we call read() only once
          while True:
              data = self.read(readsize, firstline=True)
              if data:
                  # If we're at a "\r" read one extra character (which might
                  # be a "\n") to get a proper line ending. If the stream is
                  # temporarily exhausted we return the wrong line ending.
                  if (isinstance(data, str) and data.endswith("\r")) or \
                     (isinstance(data, bytes) and data.endswith(b"\r")):
                      data += self.read(size=1, chars=1)
  
              line += data
              lines = line.splitlines(keepends=True)
              if lines:
                  if len(lines) > 1:
                      # More than one line result; the first line is a full line
                      # to return
                      line = lines[0]
                      del lines[0]
                      if len(lines) > 1:
                          # cache the remaining lines
                          lines[-1] += self.charbuffer
                          self.linebuffer = lines
                          self.charbuffer = None
                      else:
                          # only one remaining line, put it back into charbuffer
                          self.charbuffer = lines[0] + self.charbuffer
                      if not keepends:
                          line = line.splitlines(keepends=False)[0]
                      break
                  line0withend = lines[0]
                  line0withoutend = lines[0].splitlines(keepends=False)[0]
                  if line0withend != line0withoutend: # We really have a line end
                      # Put the rest back together and keep it until the next call
                      self.charbuffer = self._empty_charbuffer.join(lines[1:]) + \
                                        self.charbuffer
                      if keepends:
                          line = line0withend
                      else:
                          line = line0withoutend
                      break
              # we didn't get anything or this was our only try
              if not data or size is not None:
                  if line and not keepends:
                      line = line.splitlines(keepends=False)[0]
                  break
              if readsize < 8000:
                  readsize *= 2
          return line
  
      def readlines(self, sizehint=None, keepends=True):
  
          """ Read all lines available on the input stream
              and return them as list of lines.
  
              Line breaks are implemented using the codec's decoder
              method and are included in the list entries.
  
              sizehint, if given, is ignored since there is no efficient
              way to finding the true end-of-line.
  
          """
          data = self.read()
          return data.splitlines(keepends)
  
      def reset(self):
  
          """ Resets the codec buffers used for keeping state.
  
              Note that no stream repositioning should take place.
              This method is primarily intended to be able to recover
              from decoding errors.
  
          """
          self.bytebuffer = b""
          self.charbuffer = self._empty_charbuffer
          self.linebuffer = None
  
      def seek(self, offset, whence=0):
          """ Set the input stream's current position.
  
              Resets the codec buffers used for keeping state.
          """
          self.stream.seek(offset, whence)
          self.reset()
  
      def __next__(self):
  
          """ Return the next decoded line from the input stream."""
          line = self.readline()
          if line:
              return line
          raise StopIteration
  
      def __iter__(self):
          return self
  
      def __getattr__(self, name,
                      getattr=getattr):
  
          """ Inherit all other methods from the underlying stream.
          """
          return getattr(self.stream, name)
  
      def __enter__(self):
          return self
  
      def __exit__(self, type, value, tb):
          self.stream.close()
  
  ###
  
  class StreamReaderWriter:
  
      """ StreamReaderWriter instances allow wrapping streams which
          work in both read and write modes.
  
          The design is such that one can use the factory functions
          returned by the codec.lookup() function to construct the
          instance.
  
      """
      # Optional attributes set by the file wrappers below
      encoding = 'unknown'
  
      def __init__(self, stream, Reader, Writer, errors='strict'):
  
          """ Creates a StreamReaderWriter instance.
  
              stream must be a Stream-like object.
  
              Reader, Writer must be factory functions or classes
              providing the StreamReader, StreamWriter interface resp.
  
              Error handling is done in the same way as defined for the
              StreamWriter/Readers.
  
          """
          self.stream = stream
          self.reader = Reader(stream, errors)
          self.writer = Writer(stream, errors)
          self.errors = errors
  
      def read(self, size=-1):
  
          return self.reader.read(size)
  
      def readline(self, size=None):
  
          return self.reader.readline(size)
  
      def readlines(self, sizehint=None):
  
          return self.reader.readlines(sizehint)
  
      def __next__(self):
  
          """ Return the next decoded line from the input stream."""
          return next(self.reader)
  
      def __iter__(self):
          return self
  
      def write(self, data):
  
          return self.writer.write(data)
  
      def writelines(self, list):
  
          return self.writer.writelines(list)
  
      def reset(self):
  
          self.reader.reset()
          self.writer.reset()
  
      def seek(self, offset, whence=0):
          self.stream.seek(offset, whence)
          self.reader.reset()
          if whence == 0 and offset == 0:
              self.writer.reset()
  
      def __getattr__(self, name,
                      getattr=getattr):
  
          """ Inherit all other methods from the underlying stream.
          """
          return getattr(self.stream, name)
  
      # these are needed to make "with codecs.open(...)" work properly
  
      def __enter__(self):
          return self
  
      def __exit__(self, type, value, tb):
          self.stream.close()
  
  ###
  
  class StreamRecoder:
  
      """ StreamRecoder instances provide a frontend - backend
          view of encoding data.
  
          They use the complete set of APIs returned by the
          codecs.lookup() function to implement their task.
  
          Data written to the stream is first decoded into an
          intermediate format (which is dependent on the given codec
          combination) and then written to the stream using an instance
          of the provided Writer class.
  
          In the other direction, data is read from the stream using a
          Reader instance and then return encoded data to the caller.
  
      """
      # Optional attributes set by the file wrappers below
      data_encoding = 'unknown'
      file_encoding = 'unknown'
  
      def __init__(self, stream, encode, decode, Reader, Writer,
                   errors='strict'):
  
          """ Creates a StreamRecoder instance which implements a two-way
              conversion: encode and decode work on the frontend (the
              input to .read() and output of .write()) while
              Reader and Writer work on the backend (reading and
              writing to the stream).
  
              You can use these objects to do transparent direct
              recodings from e.g. latin-1 to utf-8 and back.
  
              stream must be a file-like object.
  
              encode, decode must adhere to the Codec interface, Reader,
              Writer must be factory functions or classes providing the
              StreamReader, StreamWriter interface resp.
  
              encode and decode are needed for the frontend translation,
              Reader and Writer for the backend translation. Unicode is
              used as intermediate encoding.
  
              Error handling is done in the same way as defined for the
              StreamWriter/Readers.
  
          """
          self.stream = stream
          self.encode = encode
          self.decode = decode
          self.reader = Reader(stream, errors)
          self.writer = Writer(stream, errors)
          self.errors = errors
  
      def read(self, size=-1):
  
          data = self.reader.read(size)
          data, bytesencoded = self.encode(data, self.errors)
          return data
  
      def readline(self, size=None):
  
          if size is None:
              data = self.reader.readline()
          else:
              data = self.reader.readline(size)
          data, bytesencoded = self.encode(data, self.errors)
          return data
  
      def readlines(self, sizehint=None):
  
          data = self.reader.read()
          data, bytesencoded = self.encode(data, self.errors)
          return data.splitlines(keepends=True)
  
      def __next__(self):
  
          """ Return the next decoded line from the input stream."""
          data = next(self.reader)
          data, bytesencoded = self.encode(data, self.errors)
          return data
  
      def __iter__(self):
          return self
  
      def write(self, data):
  
          data, bytesdecoded = self.decode(data, self.errors)
          return self.writer.write(data)
  
      def writelines(self, list):
  
          data = ''.join(list)
          data, bytesdecoded = self.decode(data, self.errors)
          return self.writer.write(data)
  
      def reset(self):
  
          self.reader.reset()
          self.writer.reset()
  
      def __getattr__(self, name,
                      getattr=getattr):
  
          """ Inherit all other methods from the underlying stream.
          """
          return getattr(self.stream, name)
  
      def __enter__(self):
          return self
  
      def __exit__(self, type, value, tb):
          self.stream.close()
  
  ### Shortcuts
  
  def open(filename, mode='rb', encoding=None, errors='strict', buffering=1):
  
      """ Open an encoded file using the given mode and return
          a wrapped version providing transparent encoding/decoding.
  
          Note: The wrapped version will only accept the object format
          defined by the codecs, i.e. Unicode objects for most builtin
          codecs. Output is also codec dependent and will usually be
          Unicode as well.
  
          Files are always opened in binary mode, even if no binary mode
          was specified. This is done to avoid data loss due to encodings
          using 8-bit values. The default file mode is 'rb' meaning to
          open the file in binary read mode.
  
          encoding specifies the encoding which is to be used for the
          file.
  
          errors may be given to define the error handling. It defaults
          to 'strict' which causes ValueErrors to be raised in case an
          encoding error occurs.
  
          buffering has the same meaning as for the builtin open() API.
          It defaults to line buffered.
  
          The returned wrapped file object provides an extra attribute
          .encoding which allows querying the used encoding. This
          attribute is only available if an encoding was specified as
          parameter.
  
      """
      if encoding is not None and \
         'b' not in mode:
          # Force opening of the file in binary mode
          mode = mode + 'b'
      file = builtins.open(filename, mode, buffering)
      if encoding is None:
          return file
      info = lookup(encoding)
      srw = StreamReaderWriter(file, info.streamreader, info.streamwriter, errors)
      # Add attributes to simplify introspection
      srw.encoding = encoding
      return srw
  
  def EncodedFile(file, data_encoding, file_encoding=None, errors='strict'):
  
      """ Return a wrapped version of file which provides transparent
          encoding translation.
  
          Strings written to the wrapped file are interpreted according
          to the given data_encoding and then written to the original
          file as string using file_encoding. The intermediate encoding
          will usually be Unicode but depends on the specified codecs.
  
          Strings are read from the file using file_encoding and then
          passed back to the caller as string using data_encoding.
  
          If file_encoding is not given, it defaults to data_encoding.
  
          errors may be given to define the error handling. It defaults
          to 'strict' which causes ValueErrors to be raised in case an
          encoding error occurs.
  
          The returned wrapped file object provides two extra attributes
          .data_encoding and .file_encoding which reflect the given
          parameters of the same name. The attributes can be used for
          introspection by Python programs.
  
      """
      if file_encoding is None:
          file_encoding = data_encoding
      data_info = lookup(data_encoding)
      file_info = lookup(file_encoding)
      sr = StreamRecoder(file, data_info.encode, data_info.decode,
                         file_info.streamreader, file_info.streamwriter, errors)
      # Add attributes to simplify introspection
      sr.data_encoding = data_encoding
      sr.file_encoding = file_encoding
      return sr
  
  ### Helpers for codec lookup
  
  def getencoder(encoding):
  
      """ Lookup up the codec for the given encoding and return
          its encoder function.
  
          Raises a LookupError in case the encoding cannot be found.
  
      """
      return lookup(encoding).encode
  
  def getdecoder(encoding):
  
      """ Lookup up the codec for the given encoding and return
          its decoder function.
  
          Raises a LookupError in case the encoding cannot be found.
  
      """
      return lookup(encoding).decode
  
  def getincrementalencoder(encoding):
  
      """ Lookup up the codec for the given encoding and return
          its IncrementalEncoder class or factory function.
  
          Raises a LookupError in case the encoding cannot be found
          or the codecs doesn't provide an incremental encoder.
  
      """
      encoder = lookup(encoding).incrementalencoder
      if encoder is None:
          raise LookupError(encoding)
      return encoder
  
  def getincrementaldecoder(encoding):
  
      """ Lookup up the codec for the given encoding and return
          its IncrementalDecoder class or factory function.
  
          Raises a LookupError in case the encoding cannot be found
          or the codecs doesn't provide an incremental decoder.
  
      """
      decoder = lookup(encoding).incrementaldecoder
      if decoder is None:
          raise LookupError(encoding)
      return decoder
  
  def getreader(encoding):
  
      """ Lookup up the codec for the given encoding and return
          its StreamReader class or factory function.
  
          Raises a LookupError in case the encoding cannot be found.
  
      """
      return lookup(encoding).streamreader
  
  def getwriter(encoding):
  
      """ Lookup up the codec for the given encoding and return
          its StreamWriter class or factory function.
  
          Raises a LookupError in case the encoding cannot be found.
  
      """
      return lookup(encoding).streamwriter
  
  def iterencode(iterator, encoding, errors='strict', **kwargs):
      """
      Encoding iterator.
  
      Encodes the input strings from the iterator using a IncrementalEncoder.
  
      errors and kwargs are passed through to the IncrementalEncoder
      constructor.
      """
      encoder = getincrementalencoder(encoding)(errors, **kwargs)
      for input in iterator:
          output = encoder.encode(input)
          if output:
              yield output
      output = encoder.encode("", True)
      if output:
          yield output
  
  def iterdecode(iterator, encoding, errors='strict', **kwargs):
      """
      Decoding iterator.
  
      Decodes the input strings from the iterator using a IncrementalDecoder.
  
      errors and kwargs are passed through to the IncrementalDecoder
      constructor.
      """
      decoder = getincrementaldecoder(encoding)(errors, **kwargs)
      for input in iterator:
          output = decoder.decode(input)
          if output:
              yield output
      output = decoder.decode(b"", True)
      if output:
          yield output
  
  ### Helpers for charmap-based codecs
  
  def make_identity_dict(rng):
  
      """ make_identity_dict(rng) -> dict
  
          Return a dictionary where elements of the rng sequence are
          mapped to themselves.
  
      """
      return {i:i for i in rng}
  
  def make_encoding_map(decoding_map):
  
      """ Creates an encoding map from a decoding map.
  
          If a target mapping in the decoding map occurs multiple
          times, then that target is mapped to None (undefined mapping),
          causing an exception when encountered by the charmap codec
          during translation.
  
          One example where this happens is cp875.py which decodes
          multiple character to \u001a.
  
      """
      m = {}
      for k,v in decoding_map.items():
          if not v in m:
              m[v] = k
          else:
              m[v] = None
      return m
  
  ### error handlers
  
  try:
      strict_errors = lookup_error("strict")
      ignore_errors = lookup_error("ignore")
      replace_errors = lookup_error("replace")
      xmlcharrefreplace_errors = lookup_error("xmlcharrefreplace")
      backslashreplace_errors = lookup_error("backslashreplace")
  except LookupError:
      # In --disable-unicode builds, these error handler are missing
      strict_errors = None
      ignore_errors = None
      replace_errors = None
      xmlcharrefreplace_errors = None
      backslashreplace_errors = None
  
  # Tell modulefinder that using codecs probably needs the encodings
  # package
  _false = 0
  if _false:
      import encodings
  
  ### Tests
  
  if __name__ == '__main__':
  
      # Make stdout translate Latin-1 output into UTF-8 output
      sys.stdout = EncodedFile(sys.stdout, 'latin-1', 'utf-8')
  
      # Have stdin translate Latin-1 input into UTF-8 input
      sys.stdin = EncodedFile(sys.stdin, 'utf-8', 'latin-1')
  