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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 is_locked(self, key):
 """Returns the status of the lock of a global variable :param key: the unique key of the global variable :return: """

        key = str(key)
        if key in self.__variable_locks:
            return self.__variable_locks[key].locked()
        return False