code: def connectionLost(self, reason):
          
          if self.busName is None:
              return
  
          for cb in self._dcCallbacks:
              cb(self, reason)
  
          for d, timeout in self._pendingCalls.values():
              if timeout:
                  timeout.cancel()
              d.errback(reason)
          self._pendingCalls = {}
  
          self.objHandler.connectionLost(reason)
docs: Called when the transport loses connection to the bus