def set_jinja2(jinja2, key=_registry_key, app=None):
 app = (app or webapp2.get_app())
 app.registry[key] = jinja2

def set_jinja2 ( jinja2 , key = _registry_key , app = None ) : app = ( app or webapp2 . get_app ( ) ) app . registry [ key ] = jinja2
sets an instance of :class:jinja2 in the app registry .