text: #
  # This source file is part of the EdgeDB open source project.
  #
  # Copyright 2011-present MagicStack Inc. and the EdgeDB authors.
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #     http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  #
  
  
  from __future__ import annotations
  
  import collections.abc
  import functools
  
  
  @functools.lru_cache(1024)
  def _is_container_type(cls):
      return (
          issubclass(cls, (collections.abc.Container)) and
          not issubclass(cls, (str, bytes, bytearray, memoryview))
      )
  
  
  @functools.lru_cache(1024)
  def _is_iterable_type(cls):
      return (
          issubclass(cls, collections.abc.Iterable)
      )
  
  
  def is_container(obj):
      cls = obj.__class__
      return _is_container_type(cls) and _is_iterable_type(cls)
  
  
  def is_container_type(type_):
      return isinstance(type_, type) and _is_container_type(type_)
  