This is probably a case where the prototype is non-unique rather than missing. In other words there are two or more prototypes for python3. The next release of CodeRunner will tell you exactly where the duplicates are but I'm afraid with your version of the code you have to find them manually. This can be a bit tricky if the prototypes haven't been clearly named as such, e g. by a user experimenting with custom prototypes. Post back here if you can't identify the duplicates and I'll see if I can come up with some better suggestions. But I'm on holiday using a cell phone so long explanations are a bit difficult
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unable to find prototype but it seems to be installed
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