@staticmethod
def get_enrich_query(event):
    """Allow running a query on the graph vertices

        The result of the query specified here will be added to the event in
        the 'QUERY_RESULT' field.

         Example:
         -------
          query = {'vitrage_type': 'nova.instance'}
          Before transform is called the result of running the query against
          the topology graph will be updated to event[QUERY_RESULT]
          To contain the list of all the vertices with
          vitrage_type=nova.instance
        """
    return None
