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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def ParseFileObject(self, parser_mediator, file_object):
 """Parses a DSV text file-like object. Args: parser_mediator (ParserMediator):
 mediates interactions between parsers and other components, such as storage and dfvfs. file_object (dfvfs.FileIO):
 file-like object. Raises: UnableToParseFile: when the file cannot be parsed. """

    # TODO: Replace this with detection of the file encoding via byte-order
    # marks. Also see: https://github.com/log2timeline/plaso/issues/1971
    if not self._encoding:
      self._encoding = parser_mediator.codepage

    try:
      if not self._HasExpectedLineLength(file_object):
        display_name = parser_mediator.GetDisplayName()
        raise errors.UnableToParseFile((
            '[{0:s}] Unable to parse DSV file: {1:s} with error: '
            'unexpected line length.').format(self.NAME, display_name))
    except UnicodeDecodeError as exception:
      display_name = parser_mediator.GetDisplayName()
      raise errors.UnableToParseFile(
          '[{0:s}] Unable to parse DSV file: {1:s} with error: {2!s}.'.format(
              self.NAME, display_name, exception))

    try:
      line_reader = self._CreateLineReader(file_object)
      reader = self._CreateDictReader(line_reader)
      row_offset = line_reader.tell()
      row = next(reader)
    except (StopIteration, csv.Error, UnicodeDecodeError) as exception:
      display_name = parser_mediator.GetDisplayName()
      raise errors.UnableToParseFile(
          '[{0:s}] Unable to parse DSV file: {1:s} with error: {2!s}.'.format(
              self.NAME, display_name, exception))

    number_of_columns = len(self.COLUMNS)
    number_of_records = len(row)

    if number_of_records != number_of_columns:
      display_name = parser_mediator.GetDisplayName()
      raise errors.UnableToParseFile((
          '[{0:s}] Unable to parse DSV file: {1:s}. Wrong number of '
          'records (expected: {2:d}, got: {3:d})').format(
              self.NAME, display_name, number_of_columns,
              number_of_records))

    for key, value in row.items():
      if self._MAGIC_TEST_STRING in (key, value):
        display_name = parser_mediator.GetDisplayName()
        raise errors.UnableToParseFile((
            '[{0:s}] Unable to parse DSV file: {1:s}. Signature '
            'mismatch.').format(self.NAME, display_name))

    row = self._ConvertRowToUnicode(parser_mediator, row)

    if not self.VerifyRow(parser_mediator, row):
      display_name = parser_mediator.GetDisplayName()
      raise errors.UnableToParseFile((
          '[{0:s}] Unable to parse DSV file: {1:s}. Verification '
          'failed.').format(self.NAME, display_name))

    self.ParseRow(parser_mediator, row_offset, row)
    row_offset = line_reader.tell()

    for row in reader:
      if parser_mediator.abort:
        break
      row = self._ConvertRowToUnicode(parser_mediator, row)
      self.ParseRow(parser_mediator, row_offset, row)
      row_offset = line_reader.tell()