filters.py 文件源码

def render(self, context):
        allowed = False
        for app in self.apps:

            if app.startswith('"') and app.endswith('"'):
                app = app[1:-1]

            if app.startswith("'") and app.endswith("'"):
                app = app[1:-1]

            if app in settings.INSTALLED_APPS:
                allowed = True
            else:
                break

        if allowed:
            return self.nodelist_true.render(context)
        else:
            return self.nodelist_false.render(context)