code: def authenticated(self, user_token, **validation_context):
          
          token = self.token_storage.get(user_token)
          if token and token.validate(user_token, **validation_context):
              return True
  
          return False
docs: Checks if user is authenticated using token passed in argument
  
          :param user_token: string representing token
  
          :param validation_context: Token.validate optional keyword arguments