PyQt Free Edition GPL warning doesn't check PyQt, only Qt
When using py2app to create a PyQt application, the sip recipe (sip.py) sets self.warn to True if pyqtconfig.Configuration().qt_edition == 'free'.
qt_edition refers to the distribution of Qt, not PyQt.
Qt is distributed under LGPL, PyQt is distributed under GPL, so whereas one likely can distribute open source Qt under most circumstances, one cannot distribute open source PyQt unless one's project falls completely under GPL.
If self.warn is set (which is the case when using open source Qt), the warning message that is generated reads:
== PyQt Free Edition GPL warning == Your application is including PyQt Free Edition! Please read the terms of the GPL license before distributing this application!
... regardless of the edition of PyQt. In my case, I'm using commercial PyQt with LGPL Qt, but still got this message. I'm not certain how to determine if the version of PyQt one is using is commercial or not, but I don't believe the way that it's done currently is correct.