human
Solve the following python programming problem given the following code:
def Transform(self, client, activity, callback) : 
    from activity import Activity 
    from asset_id import AssetIdUniquifier 
    from device import Device 
    def _OnUpdate(new_activity) : 
        'Delete the old activity.' 
        if Version._mutate_items : 
            activity.Delete (client, partial (callback, new_activity)) 
else : 
            callback (new_activity) 
(timestamp, device_id, uniquifier) = Activity.DeconstructActivityId (activity.activity_id) 
    if (device_id == Device.SYSTEM) : 
        if (device_id.activity_id in DisambiguateActivityIds2._unique_activity_ids) : 
            assert (uniquifier.server_id is None), (activity, uniquifier) 
            new_uniquifier = AssetIdUniquifier (uniquifier.client_id, activity.viewpoint_id) 
            new_activity_id = Activity.ConstructActivityId (timestamp, device_id, new_uniquifier) 
            new_activity_dict = activity._asdict () 
            new_activity_dict ['activity_id'] = new_activity_id 
            new_activity = Activity.CreateFromKeywords (** new_activity_dict) 
            logging.info (('%s
%s (%s/%s/%s) => %s (%s/%s/%s/%s)' % (activity, activity.activity_id, timestamp, device_id, uniquifier.client_id, new_activity_id, timestamp, device_id, new_uniquifier.client_id, new_uniquifier.server_id))) 
            if Version._mutate_items : 
                new_activity.Update (client, partial (_OnUpdate, new_activity)) 
else : 
                _OnUpdate (new_activity) 
else : 
            DisambiguateActivityIds2._unique_activity_ids.add (activity.activity_id) 
            callback (activity) 
else : 
        assert (activity.activity_id not in DisambiguateActivityIds2._unique_activity_ids), activity 
        callback (activity) 

    
    

    Fix the buggy line: if (device_id.activity_id in DisambiguateActivityIds2._unique_activity_ids) :
assistant
#Here is Python program to fix the buggy line: if (device_id.

if (activity.activity_id in DisambiguateActivityIds2._unique_activity_ids) :