Qt for Python (PySide/Shiboken)

After 5.15.2, the releases are Commercial LTS. Meaning that only people with a license can obtain the wheels. But, thanks to the KDE Free Qt Foundation agreement, before 12 months, the code of those commercial releases is available here https://download.qt.io/official_releases/QtForPython/shiboken2/ where you have the source code until 5.15.6, but you need to build it. Personally, I'd say forget about 5.15.x and try the latest from 6.x, even if there is a 5.15.x bug, it will be released in the next bug-fix release and be available to the public in about a year, so better to test 6.3.x hopefully and se if the bug is there.