code: def _assert_type_bounds_are_not_conflicting(current_type_bound, previous_type_bound,
                                              location, match_query):
      
      if all((current_type_bound is not None,
              previous_type_bound is not None,
              current_type_bound != previous_type_bound)):
          raise AssertionError(
              u'Conflicting type bounds calculated at location {}: {} vs {} '
              u'for query {}'.format(location, previous_type_bound, current_type_bound, match_query))
docs: Ensure that the two bounds either are an exact match, or one of them is None.