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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _callback(self, handle, event, channel, arg):
 """ Is called if a working event occurred. :param int handle: USB-CAN-Handle returned by the function :meth:`init_hardware`. :param int event: Event type. :param int channel: CAN channel (:data:`Channel.CHANNEL_CH0`, :data:`Channel.CHANNEL_CH1` or :data:`Channel.CHANNEL_ANY`). :param arg: Additional parameter defined with :meth:`init_hardware_ex`. """

        log.debug("Handle: %s, Event: %s, Channel: %s" % (handle, event, channel))

        if event == CbEvent.EVENT_INITHW:
            self.init_hw_event()
        elif event == CbEvent.EVENT_init_can:
            self.init_can_event(channel)
        elif event == CbEvent.EVENT_RECEIVE:
            self.can_msg_received_event(channel)
        elif event == CbEvent.EVENT_STATUS:
            self.status_event(channel)
        elif event == CbEvent.EVENT_DEINIT_CAN:
            self.deinit_can_event(channel)
        elif event == CbEvent.EVENT_DEINITHW:
            self.deinit_hw_event()