This post is simply stating the obvious. Sometimes even obvious things, in the wee hours of the morning, aren’t so.
When you specify parameters in your URLconf like:

urlpatterns = patterns(”,
url(r’^mark/(?P<id>\d+)/(?P<complete>\d+)/$’, views.mark, name=’mark’),
)

Keep in mind that each captured argument is a Python string. Even if the regex only captures integers – [...]