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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 MacOS keychain file-like object. Args: parser_mediator (ParserMediator):
 mediates interactions between parsers and other components, such as storage and dfvfs. file_object (dfvfs.FileIO):
 a file-like object. Raises: UnableToParseFile: when the file cannot be parsed. """

    try:
      file_header = self._ReadFileHeader(file_object)
    except (ValueError, errors.ParseError):
      raise errors.UnableToParseFile('Unable to parse file header.')

    tables = self._ReadTablesArray(file_object, file_header.tables_array_offset)

    table = tables.get(self._RECORD_TYPE_APPLICATION_PASSWORD, None)
    if table:
      for record in table.records:
        self._ParseApplicationPasswordRecord(parser_mediator, record)

    table = tables.get(self._RECORD_TYPE_INTERNET_PASSWORD, None)
    if table:
      for record in table.records:
        self._ParseInternetPasswordRecord(parser_mediator, record)