On https://doc.qt.io/qtforpython/shiboken2/gettingstarted.html the compilation is shown as 

python setup.py install --qmake=/path/to/qmake \
                        --build-tests \
                        --parallel=8 \
                        --verbose-build \
                        --internal-build=shiboken2-generator

However, the setup.py file does not accept --internal-build, but only --internal-build-type is accepted by setup.py. 

This is also wrong inside the pyside2 repo in sources/shiboken2/doc/gettingstarted.rst. Probably because it is generated from there..