docs: def on_close(self):
          """ method which is called every time a client disconnects """
          print 'Connection closed.'
          self.remove_client()
          
          client_count = len(self.get_clients().keys())
          new_client_message = '1 client disconnected, now we have %d %s!' % (client_count, 'client' if client_count <= 1 else 'clients')
          self.broadcast(new_client_message)