code: def notify(self, *args, **kwargs):
          '''Call all the callback handlers with given arguments.'''
          for handler in tuple(self.handlers):
              handler(*args, **kwargsf notify(self, *args, **kwargs):
          '''Call all the callback handlers with given arguments.'''
          for handler in tuple(self.handlers):
              handler(*args, **kwargs)
docs: Call all the callback handlers with given arguments.