How to Install Python 3 on Mac OS
Check out the steps below to install Python 3 on Mac OSX.
How to download Python3
You can download Python 3 by downloading from official Python website or using Homebrew package manager for macOS .
Python Official Site
1) Open up Python official download site. It looks something like the image below. Press Download Python 3.7.4 or the version you would like to download.
2) After downloading the installer, open it to install Python 3.
Python 3.7.4 installer Read Me contains the following note about Python 3 and Python 2 Co-existence. Thus, to run Python 3, you can run Python3 or Python3.X.X (a specific version that you installed on your machine). To run Python 2, you can run Python or Python2.7.
Python 3 and Python 2 Co-existence
Python.org Python 3.7 and 2.7.x versions can both be installed on your system
and will not conflict. Command names for Python 3 contain a 3 in them, python3
(or python3.7), idle3 (or idle3.7), pip3 (or pip3.7), etc. Python 2.7 command
names contain a 2 or no digit: python2 (or python2.7 or python), idle2 (or
idle2.7 or idle), etc.
3) Remove Python installer when you are done installing
4) Run python3 --version to check if Python 3 is installed.
python3 --version
# Python 3.7.4
If you install Python 3.7.X, you can also check its version using this command:
python3.7 --version
# Python 3.7.4
Homebrew
Another way to install Python 3 on Mac OS is using Homebrew package manager.
1) If you don’t have Homebrew install, you can install Homebrew by following the steps on Homebrew site. You can also use the following command to install Homebrew by copy and pasting it onto your terminal.
/usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
2) To install the latest version of Python 3, run the command below.
brew install python3
If you already have the latest Python installed, you will see something like the message below.
brew install python3
Updating Homebrew...
==> Auto-updated Homebrew!
Updated 1 tap (homebrew/core).
==> Updated Formulae
sbcl yosys
Warning: python 3.7.4 is already installed and up-to-date
To reinstall 3.7.4, run `brew reinstall python`
3) Run python3 --version to check if Python 3 is installed.
python3 --version
# Python 3.7.4
If you install Python 3.7.X, you can also check its version using this command:
python3.7 --version
# Python 3.7.4
Python 3 Shell
To open Python 3 shell from terminal, you can run Python 3.
python3
Python 3.7.4 (v3.7.4:e09359112e, Jul 8 2019, 14:54:52)
[Clang 6.0 (clang-600.0.57)] on darwin
Type "help", "copyright", "credits" or "license" for
more information.
>>> import time
>>> time.ctime()
'Thu Aug 22 20:00:00 2019'
>>> exit()
To close Python shell, you can type in exit(). The hotkeys to close it is to press Ctrl and D simultaneously.
Note that Command and D splits your Python shell view.
Note that you can still access Python 2 by running python command.
Python 3 Package Manager Pip3
Python 3 comes with its own package manager pip3. You can check out Python Package Index to look for packages that you need.
To install a package using pip, you can run pip3 install package_name.
Switch between Python 3 Versions
Python Official Site
The easier way is to download multiple versions from Python official website and run Python command with a version appeneded such as python3.7 and python3.6.
Homebrew
If you have previous versions of Python installed, you can run the following commands to check what versions you have and switch the version you need.
# list installed Python versions
brew info python
# switch to a specific Python version
brew switch python 3.6.5
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