Mako Runtime Error

8 <li>

9 <a ${'class="active"' if active == 'service_agreement' else ''} href="/service_agreement">Orange Service Agreement</a>

10 </li>

11 <li>

12 <a ${'class="active"' if active == 'service_blueagreement' else ''} href="/service_blueagreement">Blue Service Agreement</a>

13 </li>

14 <li>

15 <a ${'class="active"' if active == 'privacy_policy' else ''} href="/privacy_policy">Privacy Policy</a>

16 </li>

templates/service_agreement.html, line 11:

<li>

/home/python_27x_33x_zmq_40x_toolchain/opt/virtualenvs/django1.1/lib/python2.7/site-packages/mako/runtime.py, line 255:

return lambda *args, **kwargs:callable_(self.context, *args, **kwargs)

../static/templates/base.html, line 112:

${self.container()}

/home/python_27x_33x_zmq_40x_toolchain/opt/virtualenvs/django1.1/lib/python2.7/site-packages/mako/runtime.py, line 414:

callable_(context, *args, **kwargs)

/home/python_27x_33x_zmq_40x_toolchain/opt/virtualenvs/django1.1/lib/python2.7/site-packages/mako/runtime.py, line 381:

_exec_template(inherit, lclcontext, args=args, kwargs=kwargs)

/home/python_27x_33x_zmq_40x_toolchain/opt/virtualenvs/django1.1/lib/python2.7/site-packages/mako/runtime.py, line 364:

_render_context(template, callable_, context, *args, **_kwargs_for_callable(callable_, data))

/home/python_27x_33x_zmq_40x_toolchain/opt/virtualenvs/django1.1/lib/python2.7/site-packages/mako/template.py, line 133:

return runtime._render(self, self.callable_, args, data)

/home/so_src/pandora/www-production-trunk/webpy/spideroak.com/main/controller.py, line 77:

print tmpl.render(*args, **kwargs)

Error !