def save_model(self, request, obj, form, change):
    try:
        obj.created_by = request.user
    except:
        pass
    super().save_model(request, obj, form, change)
def save_model(self, request, obj, form, change):
    try:
        obj.created_by = request.user
    except:
        pass
    super().save_model(request, obj, form, change)