This is an old trick which could be used in the past to allow a webapp to be
written and displayed on the desktop without the need to launch a full web
Here we launch a PyQt QWebView and redirect it back at a local web service
run in the same process.
The trick is to get around the problem of the web framework and Qt both wanting
control of the primary python thread to execute their control loops. To get
around the problem each can be spawned into their own Greenlet and then forcing
a manual execution of Qt events rather than giving over control to app._exec().