Appendix Installing Python
This appendix covers
- Which versions of Python are available, and which to use
- Installing Python on your computer
Python is fairly portable software that can be compiled from source on most systems. Fortunately for you, Python is probably also available prebuilt for your system. This appendix will help you get set up with Python so you can run any of the code in this book from the command line.
Tip
If you’ve already installed a version of Python 3 on your computer, you’re in luck. There’s not much more to do here. Feel free to get back to reading, and follow along with the code in this book.
Note
If you install a version of Python 3, you will almost certainly need to use the python3 command when running code. python is reserved for a different Python installation on many operating systems (see section A.2).
The first version of Python 2.7 came out in 2010, and at the time of writing, macOS ships with Python 2.7.10, which is a few versions behind the latest Python 2.7 release. Python 2.7 will no longer be officially supported as of January 1, 2020.
If you’re already familiar with Python 2 and worry about upgrading to Python 3, know that most code changes you’ll need to make are small. When starting new projects, I recommend you use Python 3. This will set you up to write code that can last longer into the future.
Tip
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Figure A.1. The big yellow button gets you the latest Python, and you can find older versions or versions for other operating systems in the links below it.
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$ python3 Python 3.7.3 (default, Jun 17 2019, 14:09:05) [Clang 10.0.1 (clang-1001.0.46.4)] on darwin Type "help", "copyright", "credits" or "license" for more information. >>>
Try typing your favorite code snippet and see what happens:
>>> print('Hello, world!')
Hello, world!
Now you’re ready for world domination!
