parameters: (factory=Auth, key=_auth_registry_key, request=None)
return_statement: return auth
docstring: Returns an instance of :class:`Auth` from the request registry.
  
      It'll try to get it from the current request registry, and if it is not
      registered it'll be instantiated and registered. A second call to this
      function will return the same instance.
  
      :param factory:
          The callable used to build and register the instance if it is not yet
          registered. The default is the class :class:`Auth` itself.
      :param key:
          The key used to store the instance in the registry. A default is used
          if it is not set.
      :param request:
          A :class:`webapp2.Request` instance used to store the instance. The
          active request is used if it is not set.
docstring_summary: Returns an instance of :class:`Auth` from the request registry.
docstring_tokens: Returns an instance of : class : Auth from the request registry .
function: def get_auth(factory=Auth, key=_auth_registry_key, request=None):
      """Returns an instance of :class:`Auth` from the request registry.
  
      It'll try to get it from the current request registry, and if it is not
      registered it'll be instantiated and registered. A second call to this
      function will return the same instance.
  
      :param factory:
          The callable used to build and register the instance if it is not yet
          registered. The default is the class :class:`Auth` itself.
      :param key:
          The key used to store the instance in the registry. A default is used
          if it is not set.
      :param request:
          A :class:`webapp2.Request` instance used to store the instance. The
          active request is used if it is not set.
      """
      request = request or webapp2.get_request()
      auth = request.registry.get(key)
      if not auth:
          auth = request.registry[key] = factory(request)
  
      return auth
function_tokens: def get_auth ( factory = Auth , key = _auth_registry_key , request = None ) : request = request or webapp2 . get_request ( ) auth = request . registry . get ( key ) if not auth : auth = request . registry [ key ] = factory ( request ) return auth