Jinja2でテンプレートに関数を埋め込む

hello.html

Hello, {{ hoge() }} san.

main.py

#!/usr/bin/env python
# coding: utf-8
import os
import webapp2
from jinja2 import Environment, FileSystemLoader

env = Environment(loader=FileSystemLoader(os.path.dirname(__file__)))
env.globals['hoge'] = lambda: u"ほげほげ"

class SecondHandler(webapp2.RequestHandler):
    def get(self):
        template = env.get_template('hello.html')
        self.response.out.write(template.render())

app = webapp2.WSGIApplication([('/', MainHandler), debug=True)