code: async def remember(request, response, identity, **kwargs):
      
      assert isinstance(identity, str), identity
      assert identity
      identity_policy = request.config_dict.get(IDENTITY_KEY)
      if identity_policy is None:
          text = ("Security subsystem is not initialized, "
                  "call aiohttp_security.setup(...) first")
          # in order to see meaningful exception message both: on console
          # output and rendered page we add same message to *reason* and
          # *text* arguments.
          raise web.HTTPInternalServerError(reason=text, text=text)
      await identity_policy.remember(request, response, identity, **kwargs)
docs: Remember identity into response.
  
      The action is performed by identity_policy.remember()
  
      Usually the identity is stored in user cookies somehow but may be
      pushed into custom header also.