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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_values(self, **kwargs):
 """ Sets environment variables values. Usage:: True 'DOE' 'JOHN' :param \*\*kwargs: Variables : Values. :type \*\*kwargs: \* :return: Method success. :rtype: unicode :note: Any variable with a **None** value will be skipped. """


        self.__variables.update(kwargs)

        for key, value in self.__variables.iteritems():
            if value is None:
                continue
            LOGGER.debug("> Setting environment variable '{0}' with value '{1}'.".format(key, value))
            os.environ[key] = value
        return True