'Map a callback function or tasklet over the query results.
This is the asynchronous version of Query.map().'

@utils.positional(2)
def map_async(self, callback, pass_batch_into_callback=None, merge_future=None, **q_options):

    qry = self._fix_namespace()
    return tasklets.get_context().map_query(qry, callback, pass_batch_into_callback=pass_batch_into_callback, options=self._make_options(q_options), merge_future=merge_future)
