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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 unlock(self):
        "Unlock the key"
        if self.lockroutine:
            self.lockroutine.close()
            self.lockroutine = None
        if self.locked:
            self.locked = False
            self.scheduler.ignore(LockEvent.createMatcher(self.context, self.key, self))