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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 end(self):
 """End the roaster control process via thread signal. This simply sends an exit signal to the thread, and shuts it down. In order to stop monitoring, call the `set_monitor` method with false. :returns: None """

        self._process.shutdown()
        self._roasting = False
        self._roast['date'] = now_date(str=True)