UndefinedError in py:for

[anonymous]

This is the code I'm running in the Python interpreter from the Documentation:

from genshi.template import MarkupTemplate? tmpl = MarkupTemplate?(<ul xmlns:py="http://genshi.edgewall.org/">

... <li py:for="item in items">${item}</li> ... </ul>)

print(tmpl.generate(items=[1, 2, 3]))

<ul>

<li>1</li><li>2</li><li>3</li>

</ul>

And I'm getting an UndefinedError? for the variable item. If I force lenient mode, the template simply does not evaluate.