code: def remove_callback(self, name, before=None, after=None):
          
          if isinstance(name, (list, tuple)):
              for name in name:
                  self.remove_callback(name, before, after)
          elif before is None and after is None:
              del self._callback_registry[name]
          else:
              if name in self._callback_registry:
                  callback_list = self._callback_registry[name]
              else:
                  callback_list = []
                  self._callback_registry[name] = callback_list
              callback_list.remove((before, after))
              if len(callback_list) == 0:
                  # cleanup if all callbacks are gone
                  del self._callback_registry[name]
docs: Remove a beforeback, and afterback pair from this Spectator
  
          If ``before`` and ``after`` are None then all callbacks for
          the given method will be removed. Otherwise, only the exact
          callback pair will be removed.
  
          Parameters
          ----------
          name: str
              The name of the method the callback pair is associated with.
          before: None or callable
              The beforeback that was originally registered to the given method.
          after: None or callable
              The afterback that was originally registered to the given method.