<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def connectionLost(self, reason):
 """ Called when the transport loses connection to the bus """

        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)