This is what it shows me? What do I do?
The default interactive shell is now zsh.
To update your account to use zsh, please run chsh -s /bin/zsh.
For more details, please visit https://support.apple.com/kb/HT208050.
Sais-MacBook-Pro:~ sai$ python3 app.py
/Library/Frameworks/Python.framework/Versions/3.9/bin/python3: can’t open file ‘/Users/sai/app.py’: [Errno 2] No such file or directory
Sais-MacBook-Pro:~ sai$ python 3
/System/Library/Frameworks/Python.framework/Versions/2.7/Resources/Python.app/Contents/MacOS/Python: can’t open file ‘3’: [Errno 2] No such file or directory
Sais-MacBook-Pro:~ sai$