new_contents: import pytest
  import aiohttp_admin
  from aiohttp_admin.backends.mongo import MotorResource
  
  
  @pytest.fixture
  def create_admin(loop, create_app_and_client, mongo_collection,
                   document_schema):
      async def f(resource_name='test_post'):
          app, client = await create_app_and_client()
          admin = aiohttp_admin.setup(app, './')
          admin.add_resource(MotorResource(mongo_collection, document_schema,
                                           url=resource_name))
          return admin, client
      return f
  
  
  @pytest.mark.run_loop
  async def test_basic_rest(create_document, loop, create_admin):
      admin, client = await create_admin()
      document_num = 10
      await create_document(document_num)
      resp = await client.list('test_post')
      assert len(resp) == document_num
  
      entity_id = resp[0]['_id']
      entity = await client.detail('test_post', entity_id)
      assert entity == resp[0]
  
subject: add simple mongo related test case