caused by a circular import.

class MenuModelForm(BootStrapModelForm):
    class Meta:
        model = models.Menu
        # django.core.exceptions.ImproperlyConfigured:
        # The included URLconf 'PHM.urls' does not appear to have any patterns in it.
        # If you see valid patterns in the file then the issue is probably caused by a circular import.
        # 哎呀我滴個天呀，不加這個fields一直報上面的錯，必定必定要加，調了很久，報錯還看不出來。。哎呀呀
        fields = ['title', 'icon']