text: """Common IO api utilities"""
  
  import os
  import csv
  import codecs
  import mmap
  from contextlib import contextmanager, closing
  import zipfile
  
  from pandas.compat import StringIO, BytesIO, string_types, text_type
  from pandas import compat
  from pandas.io.formats.printing import pprint_thing
  import pandas.core.common as com
  from pandas.core.dtypes.common import is_number, is_file_like
  
  # compat
  from pandas.errors import (ParserError, DtypeWarning,  # noqa
                             EmptyDataError, ParserWarning)
  
  # gh-12665: Alias for now and remove later.
  CParserError = ParserError
  
  # common NA values
  # no longer excluding inf representations
  # '1.#INF','-1.#INF', '1.#INF000000',
  _NA_VALUES = {'-1.#IND', '1.#QNAN', '1.#IND', '-1.#QNAN', '#N/A N/A', '#N/A',
                'N/A', 'n/a', 'NA', '#NA', 'NULL', 'null', 'NaN', '-NaN', 'nan',
                '-nan', ''}
  
  
  if compat.PY3:
      from urllib.request import urlopen, pathname2url
      _urlopen = urlopen
      from urllib.parse import urlparse as parse_url
      from urllib.parse import (uses_relative, uses_netloc, uses_params,
                                urlencode, urljoin)
      from urllib.error import URLError
      from http.client import HTTPException  # noqa
  else:
      from urllib2 import urlopen as _urlopen
      from urllib import urlencode, pathname2url  # noqa
      from urlparse import urlparse as parse_url
      from urlparse import uses_relative, uses_netloc, uses_params, urljoin
      from urllib2 import URLError  # noqa
      from httplib import HTTPException  # noqa
      from contextlib import contextmanager, closing  # noqa
      from functools import wraps  # noqa
  
      # @wraps(_urlopen)
      @contextmanager
      def urlopen(*args, **kwargs):
          with closing(_urlopen(*args, **kwargs)) as f:
              yield f
  
  
  _VALID_URLS = set(uses_relative + uses_netloc + uses_params)
  _VALID_URLS.discard('')
  
  
  class BaseIterator(object):
      """Subclass this and provide a "__next__()" method to obtain an iterator.
      Useful only when the object being iterated is non-reusable (e.g. OK for a
      parser, not for an in-memory table, yes for its iterator)."""
  
      def __iter__(self):
          return self
  
      def __next__(self):
          raise com.AbstractMethodError(self)
  
  
  if not compat.PY3:
      BaseIterator.next = lambda self: self.__next__()
  
  
  def _is_url(url):
      """Check to see if a URL has a valid protocol.
  
      Parameters
      ----------
      url : str or unicode
  
      Returns
      -------
      isurl : bool
          If `url` has a valid protocol return True otherwise False.
      """
      try:
          return parse_url(url).scheme in _VALID_URLS
      except Exception:
          return False
  
  
  def _expand_user(filepath_or_buffer):
      """Return the argument with an initial component of ~ or ~user
         replaced by that user's home directory.
  
      Parameters
      ----------
      filepath_or_buffer : object to be converted if possible
  
      Returns
      -------
      expanded_filepath_or_buffer : an expanded filepath or the
                                    input if not expandable
      """
      if isinstance(filepath_or_buffer, string_types):
          return os.path.expanduser(filepath_or_buffer)
      return filepath_or_buffer
  
  
  def _validate_header_arg(header):
      if isinstance(header, bool):
          raise TypeError("Passing a bool to header is invalid. "
                          "Use header=None for no header or "
                          "header=int or list-like of ints to specify "
                          "the row(s) making up the column names")
  
  
  def _stringify_path(filepath_or_buffer):
      """Attempt to convert a path-like object to a string.
  
      Parameters
      ----------
      filepath_or_buffer : object to be converted
  
      Returns
      -------
      str_filepath_or_buffer : maybe a string version of the object
  
      Notes
      -----
      Objects supporting the fspath protocol (python 3.6+) are coerced
      according to its __fspath__ method.
  
      For backwards compatibility with older pythons, pathlib.Path and
      py.path objects are specially coerced.
  
      Any other object is passed through unchanged, which includes bytes,
      strings, buffers, or anything else that's not even path-like.
      """
      try:
          import pathlib
          _PATHLIB_INSTALLED = True
      except ImportError:
          _PATHLIB_INSTALLED = False
  
      try:
          from py.path import local as LocalPath
          _PY_PATH_INSTALLED = True
      except ImportError:
          _PY_PATH_INSTALLED = False
  
      if hasattr(filepath_or_buffer, '__fspath__'):
          return filepath_or_buffer.__fspath__()
      if _PATHLIB_INSTALLED and isinstance(filepath_or_buffer, pathlib.Path):
          return text_type(filepath_or_buffer)
      if _PY_PATH_INSTALLED and isinstance(filepath_or_buffer, LocalPath):
          return filepath_or_buffer.strpath
      return filepath_or_buffer
  
  
  def is_s3_url(url):
      """Check for an s3, s3n, or s3a url"""
      try:
          return parse_url(url).scheme in ['s3', 's3n', 's3a']
      except Exception:
          return False
  
  
  def is_gcs_url(url):
      """Check for a gcs url"""
      try:
          return parse_url(url).scheme in ['gcs', 'gs']
      except Exception:
          return False
  
  
  def get_filepath_or_buffer(filepath_or_buffer, encoding=None,
                             compression=None, mode=None):
      """
      If the filepath_or_buffer is a url, translate and return the buffer.
      Otherwise passthrough.
  
      Parameters
      ----------
      filepath_or_buffer : a url, filepath (str, py.path.local or pathlib.Path),
                           or buffer
      encoding : the encoding to use to decode py3 bytes, default is 'utf-8'
      mode : str, optional
  
      Returns
      -------
      tuple of ({a filepath_ or buffer or S3File instance},
                encoding, str,
                compression, str,
                should_close, bool)
      """
      filepath_or_buffer = _stringify_path(filepath_or_buffer)
  
      if _is_url(filepath_or_buffer):
          req = _urlopen(filepath_or_buffer)
          content_encoding = req.headers.get('Content-Encoding', None)
          if content_encoding == 'gzip':
              # Override compression based on Content-Encoding header
              compression = 'gzip'
          reader = BytesIO(req.read())
          req.close()
          return reader, encoding, compression, True
  
      if is_s3_url(filepath_or_buffer):
          from pandas.io import s3
          return s3.get_filepath_or_buffer(filepath_or_buffer,
                                           encoding=encoding,
                                           compression=compression,
                                           mode=mode)
  
      if is_gcs_url(filepath_or_buffer):
          from pandas.io import gcs
          return gcs.get_filepath_or_buffer(filepath_or_buffer,
                                            encoding=encoding,
                                            compression=compression,
                                            mode=mode)
  
      if isinstance(filepath_or_buffer, (compat.string_types,
                                         compat.binary_type,
                                         mmap.mmap)):
          return _expand_user(filepath_or_buffer), None, compression, False
  
      if not is_file_like(filepath_or_buffer):
          msg = "Invalid file path or buffer object type: {_type}"
          raise ValueError(msg.format(_type=type(filepath_or_buffer)))
  
      return filepath_or_buffer, None, compression, False
  
  
  def file_path_to_url(path):
      """
      converts an absolute native path to a FILE URL.
  
      Parameters
      ----------
      path : a path in native format
  
      Returns
      -------
      a valid FILE URL
      """
      return urljoin('file:', pathname2url(path))
  
  
  _compression_to_extension = {
      'gzip': '.gz',
      'bz2': '.bz2',
      'zip': '.zip',
      'xz': '.xz',
  }
  
  
  def _infer_compression(filepath_or_buffer, compression):
      """
      Get the compression method for filepath_or_buffer. If compression='infer',
      the inferred compression method is returned. Otherwise, the input
      compression method is returned unchanged, unless it's invalid, in which
      case an error is raised.
  
      Parameters
      ----------
      filepath_or_buffer :
          a path (str) or buffer
      compression : {'infer', 'gzip', 'bz2', 'zip', 'xz', None}
          If 'infer' and `filepath_or_buffer` is path-like, then detect
          compression from the following extensions: '.gz', '.bz2', '.zip',
          or '.xz' (otherwise no compression).
  
      Returns
      -------
      string or None :
          compression method
  
      Raises
      ------
      ValueError on invalid compression specified
      """
  
      # No compression has been explicitly specified
      if compression is None:
          return None
  
      # Infer compression
      if compression == 'infer':
          # Convert all path types (e.g. pathlib.Path) to strings
          filepath_or_buffer = _stringify_path(filepath_or_buffer)
          if not isinstance(filepath_or_buffer, compat.string_types):
              # Cannot infer compression of a buffer, assume no compression
              return None
  
          # Infer compression from the filename/URL extension
          for compression, extension in _compression_to_extension.items():
              if filepath_or_buffer.endswith(extension):
                  return compression
          return None
  
      # Compression has been specified. Check that it's valid
      if compression in _compression_to_extension:
          return compression
  
      msg = 'Unrecognized compression type: {}'.format(compression)
      valid = ['infer', None] + sorted(_compression_to_extension)
      msg += '\nValid compression types are {}'.format(valid)
      raise ValueError(msg)
  
  
  def _get_handle(path_or_buf, mode, encoding=None, compression=None,
                  memory_map=False, is_text=True):
      """
      Get file handle for given path/buffer and mode.
  
      Parameters
      ----------
      path_or_buf :
          a path (str) or buffer
      mode : str
          mode to open path_or_buf with
      encoding : str or None
      compression : {'infer', 'gzip', 'bz2', 'zip', 'xz', None}, default None
          If 'infer' and `filepath_or_buffer` is path-like, then detect
          compression from the following extensions: '.gz', '.bz2', '.zip',
          or '.xz' (otherwise no compression).
      memory_map : boolean, default False
          See parsers._parser_params for more information.
      is_text : boolean, default True
          whether file/buffer is in text format (csv, json, etc.), or in binary
          mode (pickle, etc.)
  
      Returns
      -------
      f : file-like
          A file-like object
      handles : list of file-like objects
          A list of file-like object that were opened in this function.
      """
      try:
          from s3fs import S3File
          need_text_wrapping = (BytesIO, S3File)
      except ImportError:
          need_text_wrapping = (BytesIO,)
  
      handles = list()
      f = path_or_buf
  
      # Convert pathlib.Path/py.path.local or string
      path_or_buf = _stringify_path(path_or_buf)
      is_path = isinstance(path_or_buf, compat.string_types)
  
      if is_path:
          compression = _infer_compression(path_or_buf, compression)
  
      if compression:
  
          if compat.PY2 and not is_path and encoding:
              msg = 'compression with encoding is not yet supported in Python 2'
              raise ValueError(msg)
  
          # GZ Compression
          if compression == 'gzip':
              import gzip
              if is_path:
                  f = gzip.open(path_or_buf, mode)
              else:
                  f = gzip.GzipFile(fileobj=path_or_buf)
  
          # BZ Compression
          elif compression == 'bz2':
              import bz2
              if is_path:
                  f = bz2.BZ2File(path_or_buf, mode)
              elif compat.PY2:
                  # Python 2's bz2 module can't take file objects, so have to
                  # run through decompress manually
                  f = StringIO(bz2.decompress(path_or_buf.read()))
                  path_or_buf.close()
              else:
                  f = bz2.BZ2File(path_or_buf)
  
          # ZIP Compression
          elif compression == 'zip':
              zf = BytesZipFile(path_or_buf, mode)
              # Ensure the container is closed as well.
              handles.append(zf)
              if zf.mode == 'w':
                  f = zf
              elif zf.mode == 'r':
                  zip_names = zf.namelist()
                  if len(zip_names) == 1:
                      f = zf.open(zip_names.pop())
                  elif len(zip_names) == 0:
                      raise ValueError('Zero files found in ZIP file {}'
                                       .format(path_or_buf))
                  else:
                      raise ValueError('Multiple files found in ZIP file.'
                                       ' Only one file per ZIP: {}'
                                       .format(zip_names))
  
          # XZ Compression
          elif compression == 'xz':
              lzma = compat.import_lzma()
              f = lzma.LZMAFile(path_or_buf, mode)
  
          # Unrecognized Compression
          else:
              msg = 'Unrecognized compression type: {}'.format(compression)
              raise ValueError(msg)
  
          handles.append(f)
  
      elif is_path:
          if compat.PY2:
              # Python 2
              f = open(path_or_buf, mode)
          elif encoding:
              # Python 3 and encoding
              f = open(path_or_buf, mode, encoding=encoding)
          elif is_text:
              # Python 3 and no explicit encoding
              f = open(path_or_buf, mode, errors='replace')
          else:
              # Python 3 and binary mode
              f = open(path_or_buf, mode)
          handles.append(f)
  
      # in Python 3, convert BytesIO or fileobjects passed with an encoding
      if compat.PY3 and is_text and\
              (compression or isinstance(f, need_text_wrapping)):
          from io import TextIOWrapper
          f = TextIOWrapper(f, encoding=encoding)
          handles.append(f)
  
      if memory_map and hasattr(f, 'fileno'):
          try:
              g = MMapWrapper(f)
              f.close()
              f = g
          except Exception:
              # we catch any errors that may have occurred
              # because that is consistent with the lower-level
              # functionality of the C engine (pd.read_csv), so
              # leave the file handler as is then
              pass
  
      return f, handles
  
  
  class BytesZipFile(zipfile.ZipFile, BytesIO):
      """
      Wrapper for standard library class ZipFile and allow the returned file-like
      handle to accept byte strings via `write` method.
  
      BytesIO provides attributes of file-like object and ZipFile.writestr writes
      bytes strings into a member of the archive.
      """
      # GH 17778
      def __init__(self, file, mode, compression=zipfile.ZIP_DEFLATED, **kwargs):
          if mode in ['wb', 'rb']:
              mode = mode.replace('b', '')
          super(BytesZipFile, self).__init__(file, mode, compression, **kwargs)
  
      def write(self, data):
          super(BytesZipFile, self).writestr(self.filename, data)
  
      @property
      def closed(self):
          return self.fp is None
  
  
  class MMapWrapper(BaseIterator):
      """
      Wrapper for the Python's mmap class so that it can be properly read in
      by Python's csv.reader class.
  
      Parameters
      ----------
      f : file object
          File object to be mapped onto memory. Must support the 'fileno'
          method or have an equivalent attribute
  
      """
  
      def __init__(self, f):
          self.mmap = mmap.mmap(f.fileno(), 0, access=mmap.ACCESS_READ)
  
      def __getattr__(self, name):
          return getattr(self.mmap, name)
  
      def __iter__(self):
          return self
  
      def __next__(self):
          newline = self.mmap.readline()
  
          # readline returns bytes, not str, in Python 3,
          # but Python's CSV reader expects str, so convert
          # the output to str before continuing
          if compat.PY3:
              newline = compat.bytes_to_str(newline)
  
          # mmap doesn't raise if reading past the allocated
          # data but instead returns an empty string, so raise
          # if that is returned
          if newline == '':
              raise StopIteration
          return newline
  
  
  if not compat.PY3:
      MMapWrapper.next = lambda self: self.__next__()
  
  
  class UTF8Recoder(BaseIterator):
  
      """
      Iterator that reads an encoded stream and reencodes the input to UTF-8
      """
  
      def __init__(self, f, encoding):
          self.reader = codecs.getreader(encoding)(f)
  
      def read(self, bytes=-1):
          return self.reader.read(bytes).encode("utf-8")
  
      def readline(self):
          return self.reader.readline().encode("utf-8")
  
      def next(self):
          return next(self.reader).encode("utf-8")
  
  
  if compat.PY3:  # pragma: no cover
      def UnicodeReader(f, dialect=csv.excel, encoding="utf-8", **kwds):
          # ignore encoding
          return csv.reader(f, dialect=dialect, **kwds)
  
      def UnicodeWriter(f, dialect=csv.excel, encoding="utf-8", **kwds):
          return csv.writer(f, dialect=dialect, **kwds)
  else:
      class UnicodeReader(BaseIterator):
  
          """
          A CSV reader which will iterate over lines in the CSV file "f",
          which is encoded in the given encoding.
  
          On Python 3, this is replaced (below) by csv.reader, which handles
          unicode.
          """
  
          def __init__(self, f, dialect=csv.excel, encoding="utf-8", **kwds):
              f = UTF8Recoder(f, encoding)
              self.reader = csv.reader(f, dialect=dialect, **kwds)
  
          def __next__(self):
              row = next(self.reader)
              return [compat.text_type(s, "utf-8") for s in row]
  
      class UnicodeWriter(object):
  
          """
          A CSV writer which will write rows to CSV file "f",
          which is encoded in the given encoding.
          """
  
          def __init__(self, f, dialect=csv.excel, encoding="utf-8", **kwds):
              # Redirect output to a queue
              self.queue = StringIO()
              self.writer = csv.writer(self.queue, dialect=dialect, **kwds)
              self.stream = f
              self.encoder = codecs.getincrementalencoder(encoding)()
              self.quoting = kwds.get("quoting", None)
  
          def writerow(self, row):
              def _check_as_is(x):
                  return (self.quoting == csv.QUOTE_NONNUMERIC and
                          is_number(x)) or isinstance(x, str)
  
              row = [x if _check_as_is(x)
                     else pprint_thing(x).encode("utf-8") for x in row]
  
              self.writer.writerow([s for s in row])
              # Fetch UTF-8 output from the queue ...
              data = self.queue.getvalue()
              data = data.decode("utf-8")
              # ... and re-encode it into the target encoding
              data = self.encoder.encode(data)
              # write to the target stream
              self.stream.write(data)
              # empty queue
              self.queue.truncate(0)
  
          def writerows(self, rows):
              def _check_as_is(x):
                  return (self.quoting == csv.QUOTE_NONNUMERIC and
                          is_number(x)) or isinstance(x, str)
  
              for i, row in enumerate(rows):
                  rows[i] = [x if _check_as_is(x)
                             else pprint_thing(x).encode("utf-8") for x in row]
  
              self.writer.writerows([[s for s in row] for row in rows])
              # Fetch UTF-8 output from the queue ...
              data = self.queue.getvalue()
              data = data.decode("utf-8")
              # ... and re-encode it into the target encoding
              data = self.encoder.encode(data)
              # write to the target stream
              self.stream.write(data)
              # empty queue
              self.queue.truncate(0)
  