code: def remove_all_listeners(self, event=None):
          
          if event is None:
              self._listeners = collections.defaultdict(list)
              self._once = collections.defaultdict(list)
          else:
              del self._listeners[event]
              del self._once[event]
docs: Remove all listeners, or those of the specified *event*.
  
          It's not a good idea to remove listeners that were added elsewhere in
          the code, especially when it's on an emitter that you didn't create
          (e.g. sockets or file streams).