solution or workaround?Set Python_FIND_STRATEGY to LOCATION. Or set policy CMP0094 to NEW. Or require CMake version >= 3.15.
With this, CMake finds Python 3.9 even if some 3.10 modules are present on the system.
Amyway, I still think that a Debian package should be able to **support** different Py minor versions without **depending** on them. It should only depend on the default Py version, which is defined by packages python3, python3-minimal etc. - Joachim