You then need a license for QT, which is LGPL or commercial. You can use the LGPL version of Qt with commercial PyQt, but I never understood the hoops you might have to jump through in order to comply with the LGPL. Packaging python apps is painful enough without having to worry about that, might as well spend a little to avoid the aggravation. LGPL Qt also lacks a few advanced packages.
Pyside/"Qt for Python" is LGPL.
You then need a license for QT, which is LGPL or commercial. You can use the LGPL version of Qt with commercial PyQt, but I never understood the hoops you might have to jump through in order to comply with the LGPL. Packaging python apps is painful enough without having to worry about that, might as well spend a little to avoid the aggravation. LGPL Qt also lacks a few advanced packages.