code: def step_impl04(context):
      
      single = context.singleStore
      general = context.generalStore
      key = 13
      item = 42
      assert single.request(key) == general.request(key)
      single.add_item(key, item)
      general.add_item(key, item)
      assert single.request(key) == general.request(key)
docs: Compare behavior of singleton vs. non-singleton.
  
      :param context: test context.