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Solve the following problem using Python, implementing the functions described below, one line at a time
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<USER_TASK:>
Description:
 def add_user(cls, username, email):
 """ Add user to service """

        sanitized = str(cls.__sanitize_username(username))
        logger.debug("Adding user to SeAT with username %s" % sanitized)
        password = cls.__generate_random_pass()
        ret = cls.exec_request('user', 'post', username=sanitized, email=str(email), password=password)
        logger.debug(ret)
        if cls._response_ok(ret):
            logger.info("Added SeAT user with username %s" % sanitized)
            return sanitized, password
        logger.info("Failed to add SeAT user with username %s" % sanitized)
        return None, None