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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 _shutdown(self, cancel, cancel_msg, exc_type=CancelledError):
        ''' Internal shutdown used by 'shutdown' method  above '''
        if cancel:
            # Cancel all in-flight transfers if requested, before waiting
            # for them to complete.
            self._coordinator_controller.cancel(cancel_msg, exc_type)
        try:
            # Wait until there are no more in-progress transfers. This is
            # wrapped in a try statement because this can be interrupted
            # with a KeyboardInterrupt that needs to be caught.
            self._coordinator_controller.wait()
        except KeyboardInterrupt:
            # If not errors were raised in the try block, the cancel should
            # have no coordinators it needs to run cancel on. If there was
            # an error raised in the try statement we want to cancel all of
            # the inflight transfers before shutting down to speed that
            # process up.
            self._coordinator_controller.cancel('KeyboardInterrupt()')
            raise
        finally:
            self._coordinator_controller.cleanup()