It was easy to reproduce exactly what you are seeing. I went ahead and installed Python 3.10 in a factory-fresh VM to test it. The developers are most likely unfamiliar with security developments on macOS over the past several years. There aren't very many people using IDLE on the Mac and most issues follow the same pattern as what you are currently experiencing. It isn't that there are incompatibilities, per se, between macOS and Python.
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If you apply a system update hoping to fix a bug, you are already on the wrong path.) (For the record, macOS system update NEVER fix bugs. That doesn't sound like Monterey is at all related. Well that thread you linked to was started almost two years ago, and says the issue was resolved before Monterey was ever released to anyone. py files but I thought I should mention it here in case someone runs into it before it is resolved.
PYTHON DOWNLOAD MAC IDLE WINDOWS
py files then open edit windows for them as expected. Without more detailed investigation, this appears to be a minor problem (possibly a change in Tk) unrelated to those in this issue other than that it involves double-clicking on. With IDLE.app now active, double-clicking again on the same file then does cause the file to be opened in an edit window of the active IDLE as expected and double-clicking on other. py file without IDLE.app being active, a message window appears saying that the application cannot open Python Script files but does launch IDLE.app. With the macOS 11 Big Sur / 3.10.0a4 / 8.6.11 combo, when double-clicking on a.
On macOS 11 Big Sur, there is one noticeable difference in behavior between the two. The principal difference between the 3.9.1 and 3.10.0a4 versions I tested with is that the 3.9.1 is linked with Tk 8.6.10 while 3.10.0a4 is linked with the just-released Tk 8.6.11. Now just to make things a bit more complicated - sigh: I also tested with the recent installer for the 3.10.0a4 pre-release. I believe this entry from summarises my issue best: Other posts online suggested this could be an OS issue I tried upgrading to Monterey but the issue is still present. Unfortunately, I have already checked System Preferences> Privacy settings and I can see Python is granted access to documents. I have seen similar issues online but I am yet to find a solution that works. However, when IDLE is not already open, I get an error message saying “The document could not be opened.IDLE cannot open files in the python script format”. Hello, whenever I have IDLE open, I can right click a python script in finder and open with IDLE.