And there it is...
The "final" version.Not the best game in this competition, but I've only wanted to create a little game - my first one, using python and pygame. All the features I've planned are present, though the sound can't be turned on again after turning it off. Regarding the game lasts only for one or two minutes, it's not that frustrating.
What next? Judging other entries, maybe creating the Windows executable just for the purpose of showing the game to less tech-savvy friends. It was fun, and I'm going to participate in PyWeek #10.