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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 set_value(self, format, *args):
 """ Set new value for config item. The new value may be a string, a printf format, or NULL. Note that if string may possibly contain '%', or if it comes from an insecure source, you must use '%s' as the format, followed by the string. """

        return lib.zconfig_set_value(self._as_parameter_, format, *args)