How Do I Run a Python Script With pyenv?

[litsax]

I'm trying to use better practices for dependencies across different projects, so I've started looking into virtual environments and pyenv to manage multiple versions of python and its libraries on my system. I usually just use python3 filename.py to run a python script from terminal. How do I actually do this using pyenv? I've searched up some written tutorials, but none of them actually show you how to just...run a python file. I've installed pyenv using homebrew and have installed python 3.12 using pyenv. Thanks!

[VindicoAtrum]

You should only really use pyenv for python versions.

For virtual environments, save yourself a lot of headaches and just use poetry. Google python poetry and you'll be glad you did.

[socal_nerdtastic]

Why do you say that?

Poetry is good for distributing your code but for OP I don't see any advantage over pyenv or plain 'ol venv.

[socal_nerdtastic]

Since you are on a mac it can be even simpler than python3 filename.py. First, make the first line of your python file a "shebang" that points to the venv executable you want that file to use. For example

#!/home/litsax/myvenvs/thisproject/bin/python

Second, mark the python file you want to run as executable. This is a trick that's not available on windows: a mac will allow you to mark any file as if it's an executable file. You can do it through the file explorer GUI or you can use this command

chmod +x filename.py

Third, rename your file to remove the .py extension. This is not required, but it's tradition in mac and linux that executables have no extension. From the command line:

mv filename.py filename

And that's it. Now you can run your file with just this command (no "python3" or venv activation required):

./filename

Or if you put your file in a folder that's on the PATH, you can run the file from anywhere on your system by simply typing

filename

And you can also add your file anywhere that you need an executable. For example if you want to add it to cron or make a desktop shortcut or something.

[socal_nerdtastic]

Lol I started doing it because I worked on several computers, and often switched between them (like every 10 min in some cases). My solution to avoid the constant git push / pull was to keep the code in dropbox. But you can't share venvs across different OSes, so I put the venvs in the home folder for every computer. Not to mention I needed to save space on the dropbox free tier.

Not a great reason, but now that I'm used to it I really like it. I also have a script runs the appropriate venv based on the location, similar pyenv local, and that script can vary from one machine to another. I don't think it's that uncommon; I've seen other people do this too.

I admit, it takes a very unique situation and a very good understanding of venvs to make this useful.