macOS, like Linux, ships with Python already installed. But you don't want to mess with the system Python (some system tools rely on it, etc.), so we'll install our own version(s). There are two ways to install Python, (1) Homebrew and (2) Pyenv. If you plan to use multiple versions of Python (e.g. 2, 3, and anaconda) then you should use pyenv.
Python 3 is the default version when installing with Homebrew, so if you want to install Python 2.7 you'll have to be explicit about it.
$ brew install python
$ brew install python@2
$ pip install --upgrade setuptools $ pip install --upgrade pip
Executable scripts from Python packages you install will be put in
/usr/local/share/python, make sure it's on your
pyenv is a Python version manager that can
manage and install different versions of Python. Works very much like
for Ruby. First, we must install
pyenv using Homebrew:
$ brew install pyenv
pyenv in the future, use
upgrade instead of
pyenv init to your shell to enable shims and autocompletion
.zshrc if you're using
$ echo 'eval "$(pyenv init -)"' >> ~/.bash_profile
Restart your shell so the path changes take effect.
$ exec $SHELL
You can now begin using
pyenv. To list the all available versions of Python,
including Anaconda, Jython, PyPy and Stackless, use:
$ pyenv install --list
Then install the desired versions:
$ pyenv install 2.7.12 $ pyenv install 3.5.2
global command to set global version(s) of Python to be used in all
shells. For example, if you prefer 2.7.12 over 3.5.2:
$ pyenv global 2.7.12 3.5.2 $ pyenv rehash
The leading version takes priority. All installed Python versions can be
~/.pyenv/versions. Alternatively, you can run:
$ pyenv versions system (set by /Users/your_account/.pyenv/version) * 2.7.12 * 3.5.2
This shows an asterisk
* next to the currently active version.
Application-specific Python version
local command will set local application-specific Python version(s) by
writing the version name to a
.python-version file in the current directory.
This version overrides the global version. For example, to install
$ pyenv install anaconda3-4.1.1 $ cd path/to/directory $ pyenv local anaconda3-4.1.1 $ pyenv rehash $ pyenv versions system 2.7.12 3.5.2 * anaconda3-4.1.1 (set by /Users/your_account/path/to/directory/.python-version)