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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 _ParseDataStreamWithParser( self, parser_mediator, parser, file_entry, data_stream_name):
 """Parses a data stream of a file entry with a specific parser. Args: parser_mediator (ParserMediator):
 parser mediator. parser (BaseParser):
 parser. file_entry (dfvfs.FileEntry):
 file entry. data_stream_name (str):
 data stream name. Raises: RuntimeError: if the file-like object is missing. """

    file_object = file_entry.GetFileObject(data_stream_name=data_stream_name)
    if not file_object:
      raise RuntimeError(
          'Unable to retrieve file-like object from file entry.')

    try:
      self._ParseFileEntryWithParser(
          parser_mediator, parser, file_entry, file_object=file_object)

    finally:
      file_object.close()