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@RecursiveNeuron I'm going to guess it's an error, because Python doesn't have the ++ operator.
If it turns out Python added it when I wasn't looking, and it behaves like other languages, it will print 3 twice.
Testing it out on Python 3.10.1, I'm surprised to learn that Python has a unary + operator, which (in this case) does nothing. The code therefore prints 2 twice.
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@peterdrake @RecursiveNeuron thank you very much.