def _get_from_querystring(self, environ):
        if environ.get('QUERY_STRING', '') in self.querystring_param:
            args = url_decode(environ['QUERY_STRING'])
            return args.get(self.querystring_param)
        return None
dataset/ETHPy150Open LeightonStreet/LingoBarter/lingobarter/core/middleware.py/HTTPMethodOverrideMiddleware._get_from_querystring/swapped operands of `in`