我的模板中有这个：
<h2>
Users ({{ users|length }})
</h2>
而且我还有一个循环显示用户行：
{% for user in users %}
<tr>
<td>
{{ user.email }}
etc...
</td>
</tr>
{% endfor %}
我看不到我在做什么错。用户表效果很好。但是，当我用长度过滤器添加h2时，出现此错误：
Traceback (most recent call last):
File "/Users/sean/Projects/appcash.me/_git/www/bottle.py", line 856, in _handle
return route.call(**args)
File "/Users/sean/Projects/appcash.me/_git/www/bottle.py", line 1721, in wrapper
rv = callback(*a, **ka)
File "/Users/sean/Projects/appcash.me/_git/www/views/admin.py", line 27, in custom_admin_page
return template('admin/users.html', users=users)
File "/Users/sean/Projects/appcash.me/_git/www/bottle.py", line 3487, in template
return TEMPLATES[tplid].render(kwargs)
File "/Users/sean/Projects/appcash.me/_git/www/datafly/core.py", line 184, in render
return self.tpl.render(**_defaults)
File "/Users/sean/Projects/appcash.me/_git/venv/lib/python2.7/site-packages/jinja2/environment.py", line 969, in render …