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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_variable(self, key, access_key, force=False):
 """Unlocks a global variable :param key: the key of the global variable to be unlocked :param access_key: the access key to be able to unlock the global variable :param force: if the variable should be unlocked forcefully :raises exceptions.AttributeError: if the global variable does not exist :raises exceptions.RuntimeError: if the wrong access key is passed """

        key = str(key)
        if self.__access_keys[key] == access_key or force:
            if key in self.__variable_locks:
                if self.is_locked(key):
                    self.__variable_locks[key].release()
                    return True
                else:
                    logger.error("Global variable {} is not locked, thus cannot unlock it".format(str(key)))
                    return False
            else:
                raise AttributeError("Global variable %s does not exist!" % str(key))
        else:
            raise RuntimeError("Wrong access key for accessing global variable")