Python IDLE not Running

Python 3 uses a binary named idle3, and by using the Python.org installer that binary is in /usr/local/bin and points back to idle3 in /Library/Frameworks/Python.framework/Versions/3.12/bin. The Apple command-line tools for Xcode do not install idle3 in its Python 3.9.6 distribution.

My PATH statement in my ˜/.zshrc file is:

export PATH=".:$HOME/bin:/Library/Frameworks/Python.framework/Versions/3.12/bin:${PATH}



and my invocation of idle3, not as a replacement for a proper Python syntax aware programmer's editor:

idle3 &

and that begets:

I am using Sonoma 14.3.

Check which Python is in your PATH, and confirm it's the newest and not the older one that arrives with Xcode and the command-line tools.

I never attempt to open an existing Python script in idle3. I only use idle3 to test syntax for specific lines of code or functions, and then implement those when satisfied in a proper programmer's editor (e.g. Sublime Text 4) that has a Python script open in it. Thus, I cannot reproduce your Invalid decimal literal dialog here.