The <code>uri</code> keyword is already part of the <code>**dargs</code> usage specification .  It's designed to work along with the <code>connect_uri</code> Cartesian parameter.  So I think the only parameter you need here is just <code>options</code>.  Just use <code>dargs.get('uri', None)</code> to retrieve the value.  If it's <code>None</code> then you can raise an exception or take other appropriate action.