How do I use brew installed Python as the default Python?
I try to switch to Homebrew (after using fink and macport) on Mac OS X 10.6.2. I have installed python 2.7 with
开发者_如何学Pythonbrew install python
The problem is that, contrary to Macport, it seems that there is no python_select utility, and my default mac python is always default
which python
give me
/usr/bin/python
and /usr/bin/python
is not a symlink
How can I do to make python brew flavour to be my default python ?
As suggested by the homebrew installer itself, be sure to add this to your .bashrc
or .zshrc
:
export PATH="/usr/local/opt/python/libexec/bin:$PATH"
As you are using Homebrew the following command gives a better picture:
brew doctor
Output:
==> /usr/bin occurs before /usr/local/bin This means that system-provided programs will be used instead of those provided by Homebrew. This is an issue if you eg. brew installed Python.
Consider editing your .bash_profile to put: /usr/local/bin ahead of /usr/bin in your $PATH.
See: How to symlink python in Homebrew?
$ brew link --overwrite python
Linking /usr/local/Cellar/python/2.7.3... 28 symlinks created
$ which python
/usr/local/bin/python
Quick fix:
- Open
/etc/paths
- Change the order of the lines (highest priority on top)
In my case /etc/paths
looks like:
/usr/local/bin
/usr/local/sbin
/usr/bin
/bin
/usr/sbin
/sbin
If you want to know more about paths in OSX I found this article quite useful:
http://muttsnutts.github.com/blog/2011/09/12/manage-path-on-mac-os-x-lion/
I did "brew install python" for OSX High Sierra. The $PATH
had /usr/local/bin
before any other path but still which python
was pointing to the system's python.
When I looked deeper I found that there is no python executable at /usr/local/bin
. The executable is named python2
. To fix this problem create a symbolic link python
pointing to python2
:
/usr/local/bin $: ln -s python2 python
For Apple Silicon machines, the path are slightly different. After running brew install python
, you must ensure your ~/.zshrc
uses the correct Homebrew paths:
# Homebrew
eval "$(/opt/homebrew/bin/brew shellenv)"
# Homebrew: Python
export PATH="/opt/homebrew/opt/python/libexec/bin:$PATH"
Results:
% which python
/opt/homebrew/opt/python/libexec/bin/python
% python --version
Python 3.9.9
% which pip
/opt/homebrew/opt/python/libexec/bin/pip
% pip -V
pip 21.3.1 from /opt/homebrew/lib/python3.9/site-packages/pip (python 3.9)
python
formula now uses python3
(v3.6.5 for now), brew will link the directory:
/usr/local/opt/python -> ../Cellar/python/3.6.5
it will also link the binary:
/usr/local/bin/python3 -> ../Cellar/python/3.6.5/bin/python3
If you still need to use python2.x
, use:
brew install python@2
To use homebrew's python
, just put its directory in PATH, for bash:
export PATH="/usr/local/opt/python/libexec/bin:$PATH"
for fish:
set -x PATH /usr/local/opt/python/libexec/bin $PATH
Note:
- doing this will shadow the system default version of
python
- homebrew used to link python to
/usr/local/share/python
in older versions.
Homebrew does NOT replace stuff in "/usr/bin". You'll just want to put "/usr/local/bin" ahead of "/usr/bin" in your path, then "which python" will give you "/usr/local/bin/python".
Replacing /usr/bin/python (or /usr/bin/ruby) is highly unrecommended.
Modify your $PATH, Add this in your bashrc or bash_profile:
export PATH=/usr/local/bin:/usr/local/sbin:~/bin:$PATH
more click here: Issue #89791
I did brew install python
, my $PATH
was good, but still, which python
gave me the system installed one. Restarting the terminal fixed it.
You need to edit your PATH environmental variable to make sure wherever the homebrew python is located is searched before /usr/bin. You could also set things up in your shell config to have a variable like PYTHON be set to your desired version of python and call $PYTHON
rather than python
from the command line.
Also, as another poster stated (and especially on mac) DO NOT mess with the python in /usr/bin to point it to another python install. You're just asking for trouble if you do.
python
now points to python3
, if you need python 2
then do:
brew install python@2
and then in your .zshrc or .bashrc file
export PATH="/usr/local/opt/python@2/libexec/bin:$PATH"
Now, pyhon --version
= Python 2.7.14 and python3 --version
= Python 3.6.4.
That's the behavior I'm used to seeing in my terminal.
I believe there are means to make homebrew python default, but in my opinion the proper way to solve a problem is not to mess with system python paths: it is better to create a virtualenv in which homebrew python would be default (by using virtualenv --python option). Using tools like python_select
is almost always a bad idea.
Use pyenv instead to install and switch between versions of Python. I've been using rbenv for years which does the same thing, but for Ruby. Before that it was hell managing versions.
Consult pyenv's github page for installation instructions. Basically it goes like this:
- Install pyenv using homebrew. brew install pyenv
- Add a function to the end of your shell startup script so pyenv can do it's magic. echo -e 'if command -v pyenv 1>/dev/null 2>&1; then\n eval "$(pyenv init -)"\nfi' >> ~/.bash_profile
- Use pyenv to install however many different versions of Python you need.
pyenv install 3.7.7
. - Set the default (global) version to a modern version you just installed.
pyenv global 3.7.7
. - If you work on a project that needs to use a different version of python, look into
pyevn local
. This creates a file in your project's folder that specifies the python version. Pyenv will look override the global python version with the version in that file.
Add the /usr/local/opt/python/libexec/bin
explicitly to your .bash_profile
:
export PATH="/usr/local/opt/python/libexec/bin:$PATH"
After that, it should work correctly.
Just do:
brew install python
brew link python
After doing that, add this to your bashrc or bash_profile:
alias python='/usr/local/bin/python2'
Enjoy!
You can edit /etc/paths. Here is mine:
/usr/local/bin
/usr/bin
/bin
/usr/sbin
/sbin
Then add a symlink for the python version. In my case
$ cd /usr/local/bin
$ ln -s python3 python
Voila!
If you are fish shell
echo 'set -g fish_user_paths "/usr/local/opt/python/libexec/bin" $fish_user_paths' >> ~/.config/fish/config.fish
try this
which python3
Try typing python3
instead of just python
Greeting folks! I have the need to use python 3.10 version to harness its new features. My solved solution at 2022-07-03 is as follows. Have fun coding python!
» rm '/usr/local/bin/pip3.10'
» brew link python@3.10
» echo 'export PATH="/usr/local/opt/python@3.10/bin:$PATH"' >> ~/.zshrc
» python3
Python 3.10.5 (main, Jun 23 2022, 17:15:25) [Clang 13.1.6 (clang-1316.0.21.2.5)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
Since High Sierra, you need to use:
sudo chown -R $(whoami) $(brew --prefix)/*
This is because /usr/local
can no longer be chowned
brew link python
And you must create/add an alias for python and put it in your .zprofile (Located in Users/username folder, if you press Shift+command+.
This must point to your homebrew python installation location.
alias python ='opt/homebrew/bin/python3'
No idea what you mean with default Python. I consider it bad practice to replace the system Python interpreter with a different version. System functionality may depend in some way on the system Python and specific modules or a specific Python version. Instead install your custom Python installations in a safe different place and adjust your $PATH as needed in order to call you Python through a path lookup instead of looking for the default Python.
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