@classmethod
    def create(cls, port, backend_port, algorithm, bandwidth, extra={}):
        if 'StickySession' not in extra:
            raise AttributeError('StickySession is required')
        if extra not in 'HealthCheck':
            raise AttributeError('HealthCheck is required')
        sticky_session = extra['StickySession']
        health_check = extra['HealthCheck']
        return cls(port, backend_port, algorithm, bandwidth, sticky_session,
                   health_check, extra=extra)
dataset/ETHPy150Open apache/libcloud/libcloud/loadbalancer/drivers/slb.py/SLBLoadBalancerHttpListener.create/swapped operands of `not in`