Mac OS X comes with Python 2.7 out of the box.
- Python Development Environment Mac
- Mac Default Python 3
- Python Environments Mac
- Python Create Virtual Environment Mac
- Python Environments For Machine Learning
Virtualenv is a tool that lets you create an isolated Python environment for your project. It creates an environment that has its own installation directories, that doesn’t share dependencies with other virtualenv environments (and optionally doesn’t access the globally installed dependencies either). Local Environment Setup. Open a terminal window and type 'python' to find out if it is already. Your First Program in Python 3 on Mac OS X. This page tells you how to setup a Python programming environment for your Mac OS X computer and provides a step-by-step guide for creating and running a simple 'Hello, world' Python program. All of the software is freely available on the Web.
You do not need to install or configure anything else to use Python 2. Theseinstructions document the installation of Python 3.
The version of Python that ships with OS X is great for learning, but it’s notgood for development. The version shipped with OS X may be out of date from theofficial current Python release,which is considered the stable production version.
Doing it Right¶
Let’s install a real version of Python.
Before installing Python, you’ll need to install GCC. GCC can be obtainedby downloading Xcode, the smallerCommand Line Tools (must have anApple account) or the even smaller OSX-GCC-Installerpackage.
Note
If you already have Xcode installed, do not install OSX-GCC-Installer.In combination, the software can cause issues that are difficult todiagnose.
Note
If you perform a fresh install of Xcode, you will also need to add thecommandline tools by running
xcode-select--install
on the terminal.While OS X comes with a large number of Unix utilities, those familiar withLinux systems will notice one key component missing: a package manager.Homebrew fills this void.
To install Homebrew, open
Terminal
oryour favorite OS X terminal emulator and runThe script will explain what changes it will make and prompt you before theinstallation begins.Once you’ve installed Homebrew, insert the Homebrew directory at the topof your
PATH
environment variable. You can do this by adding the followingline at the bottom of your ~/.profile
fileIf you have OS X 10.12 (Sierra) or older use this line instead
Now, we can install Python 3:
This will take a minute or two.
Pip¶
Homebrew installs
pip
pointing to the Homebrew’d Python 3 for you.Working with Python 3¶
At this point, you have the system Python 2.7 available, potentially theHomebrew version of Python 2 installed, and the Homebrewversion of Python 3 as well.
Python Development Environment Mac
will launch the Homebrew-installed Python 3 interpreter.
will launch the Homebrew-installed Python 2 interpreter (if any).
will launch the Homebrew-installed Python 3 interpreter.
If the Homebrew version of Python 2 is installed then
pip2
will point to Python 2.If the Homebrew version of Python 3 is installed then pip
will point to Python 3.The rest of the guide will assume that
python
references Python 3.Pipenv & Virtual Environments¶
The next step is to install Pipenv, so you can install dependencies and manage virtual environments.
A Virtual Environment is a tool to keep the dependencies required by different projectsin separate places, by creating virtual Python environments for them. It solves the“Project X depends on version 1.x but, Project Y needs 4.x” dilemma, and keepsyour global site-packages directory clean and manageable.
For example, you can work on a project which requires Django 1.10 while alsomaintaining a project which requires Django 1.8.
So, onward! To the Pipenv & Virtual Environments docs!
This page is a remixed version of another guide,which is available under the same license.
12.1. Introduction¶
Mac Default Python 3
Python applications will often use packages and modules that don’tcome as part of the standard library. Applications will sometimesneed a specific version of a library, because the application mayrequire that a particular bug has been fixed or the application may bewritten using an obsolete version of the library’s interface.
Python Environments Mac
This means it may not be possible for one Python installation to meetthe requirements of every application. If application A needs version1.0 of a particular module but application B needs version 2.0, thenthe requirements are in conflict and installing either version 1.0 or 2.0will leave one application unable to run.
Python Create Virtual Environment Mac
The solution for this problem is to create a virtual environment, aself-contained directory tree that contains a Python installation for aparticular version of Python, plus a number of additional packages.
Python Environments For Machine Learning
Different applications can then use different virtual environments.To resolve the earlier example of conflicting requirements,application A can have its own virtual environment with version 1.0installed while application B has another virtual environment with version 2.0.If application B requires a library be upgraded to version 3.0, this willnot affect application A’s environment.