Python symlink to python3 [closed]

Question

So I'm setting up my default variables in a new MacBook M1 and for some reason, my symlink doesn't seem to work.

Why is the following behaviour happening? The symlink from python to python3 gets lost somehow. /Users/overflow/Documents/tools is part of my PATH variable.

$ type python
python is /Users/overflow/Documents/tools/python

$ python -V
Python 2.7.16

$ ls -lah /Users/overflow/Documents/tools/python
lrwxr-xr-x  1 overflow  staff    16B  6 Oct 18:48 /Users/overflow/Documents/tools/python -> /usr/bin/python3

$ /usr/bin/python3 -V
Python 3.8.9

$ echo $PATH | sed 's/:/\n/g'
/Users/overflow/Documents/tools
/Users/overflow/Documents/Dropbox/productivity/bin
/Users/overflow/Documents/tools/confluent-6.1.0/bin
/Users/overflow/.sdkman/candidates/java/current/bin
/Users/overflow/.nvm/versions/node/v16.10.0/bin
/Users/overflow/bin
/usr/local/bin
/opt/homebrew/bin
/opt/homebrew/sbin
/usr/local/bin
/usr/bin
/bin
/usr/sbin
/sbin

Hammurabi

some system may still use Python 2 to run some functions and sometimes changing symlink may crush system. Better use command python3 or python3.8 to run Python 3 – Agriculture

maybe you have other command python in current folder and it may run this command instead of /Users/overflow/Documents/tools/python . Maybe you have path . on PATH so it may run command python like ./python – Agriculture

Maybe it's an alias or function... run 'type python'.. it will give you a better answer than 'which' does. – Gerous

I didn't know about type command, it's awesome! - I've just replaced the which statement with a type one. Also added my PATH there – Hammurabi

you did not show the result of : which python – Susurrate

The link you made is on python is on the directory which contains python or on python3 exe : what is important is the PATH contents which should give directory containing exe. Also check that there is not a alias python. – Susurrate

I removed the result of which but it was showing the same as type. Now, the PATH variable contains /Users/overflow/Documents/tools, which is the directory containing the "exe" you mention that is the link I've just created. I'm not sure I get what you mean by that tbh. – Hammurabi

Can we know the type of the shell with version? bash or zsh. I'm not sure if that would help in particular but it can help in narrowing down the search. – Cheyney

Run hash -r and try again. It clears a cache in shell. – Marocain

I noticed you have home-brew, so you can home-brew pyenv and set your global pyenv to whatever version you need. I use it to run 3.10.0 at the moment on my M1 – Philana

hash -r didn't solve the issue. I would like to avoid using python managers and use the default one. – Hammurabi

While I'm not sure why this is happening, might I suggest using an alias instead of a symlink? Personally, I use alias python=python3.9 and alias pip=pip3.9 in my .zshrc. This question may be of interest. – Prior

Answer 1

Given the path is not being utilized, it is being overridden by a shell alias. This can be confirmed by typing set | grep python

If you are using virtualenv:

Try: /usr/bin/python3 -m venv python3.8.9

The common MacOS python managers are:

1. pythonz

List installs using pythonz list

Change using: /usr/bin/python3 -m venv python3.8.9

2. pythonbrew

List installs pythonbrew list

Use pythonbrew switch 3.8.9 to move to the new version.

3. pyenv

Claims to use only $PATH. Included for completeness, but just in case

List installs pyenv versions

Use pyenv global 3.8.9 to move to the new version.

---

To remove any of these remove the appropriate line from your ~/.bashrc or ~/.zshrc file.

You can locate the line with grep ~/.bashrc python.

Subdiaconate

set | grep python doesn't return anything and neither of those three python managers is installed. – Hammurabi

type python would print python is an alias for ... if OP had an alias set. Since they supplied type python output in the question, I think we can safely say they do not have an alias set. – Prior

@thisisrandy, That is correct. The type output was not there when I started the answer. In that case it, is most likely the python virtual environment. – Subdiaconate

Answer 2

I can give you some general troubleshooting tips and a band-aid that can replace a symlink.

$(which python) -V

This should get you the version for python3.

Other thing worth checking:

which python2

This should point to some standard location, /usr/bin/python2 for example. If it isn't pointed there, might be worth understanding why.

In general, Macs have some quirks. The fact that a new MacBook M4 ships with Python2 as the default is a smell that you probably shouldn't try to overwrite the default value, and for whatever reason it doesn't seem to want you to.

Simple answer: set an alias.

echo 'alias python="python3"' >> ~/.zshrc && source;

This will work for you and should not interfere with any potential other systems.

Better answer:

As others have described, create a virtual environment and source venv/bin/activate.

Pricilla

+1 to 'alias python="python3"` if args[0] ends with 3, you will get a Python3 interpreter no matter what venv is set to. – Subdiaconate

Answer 3

For macOs 13 (Ventura)

Required install python3 first then set an alias for python that link to python3.

echo 'alias python="python3"' >> ~/.zshrc && source ~/.zshrc;

Esra

Answer 4

This solution is not specific to Mac, but on a .deb based system you want:

sudo apt install python-is-python3

Puppis