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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 DocumentVersionsRow( self, parser_mediator, query, row, **unused_kwargs):
 """Parses a document versions row. Args: parser_mediator (ParserMediator):
 mediates interactions between parsers and other components, such as storage and dfvfs. query (str):
 query that created the row. row (sqlite3.Row):
 row. """

    query_hash = hash(query)

    # version_path = "PerUser/UserID/xx/client_id/version_file"
    # where PerUser and UserID are a real directories.
    version_path = self._GetRowValue(query_hash, row, 'version_path')
    path = self._GetRowValue(query_hash, row, 'path')

    paths = version_path.split('/')
    if len(paths) < 2 or not paths[1].isdigit():
      user_sid = ''
    else:
      user_sid = paths[1]
    version_path = self.ROOT_VERSION_PATH + version_path
    path, _, _ = path.rpartition('/')

    event_data = MacDocumentVersionsEventData()
    # TODO: shouldn't this be a separate event?
    event_data.last_time = self._GetRowValue(query_hash, row, 'last_time')
    event_data.name = self._GetRowValue(query_hash, row, 'name')
    event_data.path = path
    event_data.query = query
    # Note that the user_sid value is expected to be a string.
    event_data.user_sid = '{0!s}'.format(user_sid)
    event_data.version_path = version_path

    timestamp = self._GetRowValue(query_hash, row, 'version_time')
    date_time = dfdatetime_posix_time.PosixTime(timestamp=timestamp)
    event = time_events.DateTimeValuesEvent(
        date_time, definitions.TIME_DESCRIPTION_CREATION)
    parser_mediator.ProduceEventWithEventData(event, event_data)