human
Solve the following python programming problem given the following code:
@ classmethod 
@ gen.coroutine 
def MuteAlerts(cls, client, user_id) : 
    'Turn off alerts to all devices owned by "user_id".' 
    @ gen.coroutine 
    def _VisitDevice(device) : 
        device.alert_user_id = None 
        (yield gen.Task (device.Update, client)) 
(yield gen.Task (Device.VisitRange, client, client, None, None, _VisitDevice)) 

    
    

    Fix the buggy line: (yield gen.Task (Device.VisitRange, client, client, None, None, _VisitDevice))
assistant
#Here is Python code to fix the buggy line: (yield gen.

(yield gen.Task (Device.VisitRange, client, user_id, None, None, _VisitDevice))