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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 _gevent_patch():
 """Patch the modules with gevent :return: Default is GEVENT. If it not supports gevent then return MULTITHREAD :rtype: int """

    try:
        assert gevent
        assert grequests
    except NameError:
        logger.warn('gevent not exist, fallback to multiprocess...')
        return MULTITHREAD
    else:
        monkey.patch_all()  # Must patch before get_photos_info
        return GEVENT