code: def _construct_where_to_match(where_block):
      
      if where_block.predicate == TrueLiteral:
          raise AssertionError(u'Received WHERE block with TrueLiteral predicate: {}'
                               .format(where_block))
      return u'WHERE ' + where_block.predicate.to_match()
docs: Transform a Filter block into a MATCH query string.