human
Solve the following python programming problem given the following code:
def patch_save(self, instance) : 
    original_save = original_save.save 
    def save(**kwargs) : 
        is_new_object = (instance.pk is None) 
        ret = original_save (** kwargs) 
        tracker = getattr (instance, self.attname) 
        field_histories = [] 
        for field in self.fields : 
            if (tracker.has_changed (field) or is_new_object) : 
                data = serializers.serialize (get_serializer_name (), [instance], fields = [field]) 
                user = self.get_field_history_user (instance) 
                history = FieldHistory (object = instance, field_name = field, serialized_data = data, user = user) 
                field_histories.append (history) 
if field_histories : 
            FieldHistory.objects.bulk_create (field_histories) 
self._inititalize_tracker (instance) 
        return ret 
instance.save = save 

    
    

    Fix the buggy line: original_save = original_save.save
assistant
#Here is Python program to fix the buggy line: original_save = original_save.

original_save = instance.save