Martin: the problematic key is "[HKEY_CLASSES_ROOT\BDATuner.Składniki]". I am pasting its name, because I suppose, that as bugs.python.org is utf-8, special characters will be pasted properly.
Included you will find a .REG file, which is Windows Registry Editor file, which is plaintext. It is encoded with CP-1250 charset (I believe). In any case of confusion, I inlcude also the same file encoded with utf-8.
If you add those information to your Windows registry, you should be able to reproduce this bug just by simply using "pip install" anything. "pip install wokkel", for example.