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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 close(self):
 """Force close all Channels and cancel all Operations """

        if self._Q is not None:
            for T in self._T:
                self._Q.interrupt()
            for n, T in enumerate(self._T):
                _log.debug('Join Context worker %d', n)
                T.join()
            _log.debug('Joined Context workers')
            self._Q, self._T = None, None
        super(Context, self).close()