code: def is_possible_type(
          self, abstract_type: GraphQLAbstractType, possible_type: GraphQLObjectType
      ) -> bool:
          
          possible_type_map = self._possible_type_map
          try:
              possible_type_names = possible_type_map[abstract_type.name]
          except KeyError:
              possible_types = self.get_possible_types(abstract_type)
              possible_type_names = {type_.name for type_ in possible_types}
              possible_type_map[abstract_type.name] = possible_type_names
          return possible_type.name in possible_type_names
docs: Check whether a concrete type is possible for an abstract type.