code: def __make_id(receiver):
      
      if __is_bound_method(receiver):
          return (id(receiver.__func__), id(receiver.__self__))
      return id(receiver)
docs: Generate an identifier for a callable signal receiver.
  
      This is used when disconnecting receivers, where we need to correctly
      establish equivalence between the input receiver and the receivers assigned
      to a signal.
  
      Args:
          receiver: A callable object.
  
      Returns:
          An identifier for the receiver.