Setting Up macOS for Python
Getting The Tools
macOS sometimes comes with Python out of the box, but not the full setup you’ll need for development or this class. It also doesn’t have the latest version, so we recommend installing a new version.
Note
If you use macports or homebrew to manage *nix software on your machine, feel free to use those for python, git, etc, as well. But make sure you have Python 3.9 or greater. If not, then read on.
Terminal
You will need a command line terminal. The built-in “terminal” application works fine. Find it in:
/Applications/Utilities/Terminal
Drag it to the dock to access more easily.
Python
While macOS oftentimes provide Python out of the box, it tends not to have the latest version, and you really don’t want to mess with the system installation. So we recommend installing an independent installation from python.org.
Download the latest release of Python installer from Python.org:
https://www.python.org/downloads/
NOTE: As of this writing, version 3.13.0 was just released – it will work fine. But we will not be using any 3.13 features in this course, and examples will generally refer to Python 3.9 – so anything between 3.9 and 3.13 should be good.
Double click the installer and follow the prompts. The defaults are your best bet. Simple as that.
Installing Python on macOS does NOT install a python command, but rather a python3 command. You can type python3 all the time or you can create an alias, like this:
alias python='python3'
You can add this to your .zsh_profile file.
The reason for setting an alias rather like this is because some installations of macOS include Python already and they map the python command to the included version of Python. You do not want to change the system version of Python.
Once you have set an alias then you should be able to type python at the command prompt and get something like:
$ python
Python 3.12.5 (main, Aug 9 2024, 08:49:33) [Clang 15.0.0 (clang-1500.3.9.4)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>>
This is the Python interpreter.
Type ctrl+D to get out (or exit())
Note
If all this is confusing to you – take heart – you will get used to it. And in the meantime, you can simply type python3 when you want to run python.
pip
pip is the Python package installer. It should be installed with Python and generally the version that comes with Python is up to date enough that you won’t need to install a newer version. Just make sure you can run pip and get back its help page.
$ python -m pip
Using pip:
To use pip to install a package, you invoke it with this command:
$ python3 -m pip install the_name_of_the_package
Where python3 is the command you use to invoke the Python you want to use.
NOTE: You will frequently see advice to use pip like so:
$ pip install something_or_other
This often works, but also can invoke the wrong version of pip. This command:
$ python3 -m pip install something_or_other
Calls Python, and tells it to run the pip module. It is exactly the same as calling pip directly, except that you are assured that you are getting the version of pip connected the version of Python that you are running.
iPython
One package we are going to use in the program from the beginning is iPython. You can install it with pip like so:
$ python3 -m pip install ipython
(It will install a LOT…)
Now you should now be able to run iPython:
$ ipython
Python 3.12.5 (main, Aug 9 2024, 08:49:33) [Clang 15.0.0 (clang-1500.3.9.4)]
Type 'copyright', 'credits' or 'license' for more information
IPython 8.26.0 -- An enhanced Interactive Python. Type '?' for help.
In [1]:
Which you can also get out of with ctrl+D or exit()
git
Git is a source code version control system. It is not strictly related to Python, but it (or a similar system) is a critical tool for software development in general, and it is very widely used in the Python community. We will be using it, along with the GitHub Classroom service, in the program to hand in assignments and support code review.
You will need a git client. The GitHub GUI client may be nice; I honestly don’t know. However, we will be using the command line client in class.
There are a couple of options for a command line client.
Perhaps the easiest way, particularly if you need a compiler for any other reason, is to get git as part of the XCode command line tools, You can install XCode from the App Store. But be forewarned – it is a VERY big download: 11.2GB!
After you have installed XCode, the git command should work.
$ git --version
git version 2.24.3 (Apple Git-128)
Testing it out
To be ready for this course, you need to have, all available from the command line:
python
pip
iPython
git
To try it out, you should be able to run all of the following commands, and get something like the results shown:
(Recall that you can get out of the python or iPython command lines with quit() or ctrl+Z. If that doesn’t work, try ctrl+D.)
For Python:
$ python3
Python 3.12.5 (main, Aug 9 2024, 08:49:33) [Clang 15.0.0 (clang-1500.3.9.4)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>>
For iPython:
$ ipython
Python 3.12.5 (main, Aug 9 2024, 08:49:33) [Clang 15.0.0 (clang-1500.3.9.4)]
Type 'copyright', 'credits' or 'license' for more information
IPython 8.26.0 -- An enhanced Interactive Python. Type '?' for help.
In [1]:
For pip:
$ python3 -m pip --version
pip 24.2 from /Library/Frameworks/Python.framework/Versions/3.12/lib/python3.12/site-packages/pip (python 3.12)
Note that when you ask pip for --version it tells you which version of python it is “connected” to.
Make sure that’s the one you expect!
For git:
$ git --version
git version 2.39.3 (Apple Git-146)
If those commands all run – you are all set!