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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 stop(self):
 """ Terminate any outstanding requests. :returns: :class:``Deferred` which fires when fully stopped. """

        self.stopping = True
        # Cancel any outstanding request to our client
        if self._batch_send_d:
            self._batch_send_d.cancel()
        # Do we have to worry about our looping call?
        if self.batch_every_t is not None:
            # Stop our looping call, and wait for the deferred to be called
            if self._sendLooper is not None:
                self._sendLooper.stop()
        # Make sure requests that wasn't cancelled above are now
        self._cancel_outstanding()
        return self._sendLooperD or succeed(None)