Since I got the macOS v12.3 (Monterey) update (not sure it's related though), I have been getting this error when I try to run my Python code in the terminal:

I am using Python 3.10.3, Atom IDE, and run the code in the terminal via atom-python-run package (which used to work perfectly fine). The settings for the package go like this:

The which command in the terminal returns the following (which is odd, because earlier it would return something to just which python):

I gather the error occurs because the terminal calls for python instead of python3, but I am super new to any coding and have no idea why it started now and how to fix it. Nothing of these has worked for me:

• I deleted and then reinstalled the Python interpreter from python.org.
• I tried alias python='python3' (which I saw in one of the threads here).
• I tried export PATH="/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin" (which I found here).
• To reset zsh and paths, I deleted all associated hidden files in /local/users/ and ran the terminal once again.
• I deleted everything and reinstalled Mac OS X and the Python interpreter only to get the same error.

OK, after a couple of days trying, this is what has worked for me:

1. I reinstalled Monterey (not sure it was essential, but I just figured I had messed with terminal and $PATH too much).
2. I installed python via brew rather than from the official website. It would still return command not found error.
3. I ran echo "alias python=/usr/bin/python3" >> ~/.zshrc in terminal to alias python with python3.

Problem solved.

As far as I get it, there is no more pre-installed python 2.x in macOS as of 12.3 hence the error. I still find it odd though that atom-python-run would call for python instead of python3 despite the settings.