REST inspect_stats and inspect_vnics cann't work when userid is a list type

>>> con.send_request('guest_inspect_stats', ['SYDYFVT1','SYDYFVT2'])
127.0.0.1 - - [05/Feb/2018 02:14:47] "POST /token HTTP/1.1" 200 0
127.0.0.1 - - [05/Feb/2018 02:14:47] "GET /guests/stats?userid=['SYDYFVT1',%20'SYDYFVT2'] HTTP/1.1" 400 264
{u'rs': 400, u'overallRC': 400, u'modID': 120, u'rc': 400, u'output': u'', u'errmsg': u'ValidationError: Validation error: Invalid input for query parameters 0. Value: [\'SYDYFVT1\', \'SYDYFVT2\']. u"[\'SYDYFVT1\', \'SYDYFVT2\']" does not match \'^(\\\\w{,8})(,\\\\w{,8}){0,}$\''}
>>>

when userid is passed as a list, the rest server would fail with the parameter schema check.