def index_list(self):
<EOL>return self._index_list<EOL>
Return the list of indexes used for this query.

        This returns a list of index representations, where an index
        representation is the same as what is returned by get_indexes().

        Before the first result, the information is unavailable, and then
        None is returned.  This is not the same as an empty list -- the
        empty list means that no index was used to execute the query.  (In
        the dev_appserver, an empty list may also mean that only built-in
        indexes were used; metadata queries also return an empty list
        here.)

        Proper use is as follows:
          q = <modelclass>.query(<filters>)
          i = q.iter()
          try:
            i.next()
          except Stopiteration:
            pass
          indexes = i.index_list()
          assert isinstance(indexes, list)

        Notes:
        - Forcing produce_cursors=False makes this always return None.
        - This always returns None for a multi-query.