Installing Python

Mac OS X & Linux

0. Make sure you have gcc installed, e.g.:

   $ xcode-select --install  # OS X
   $ sudo apt-get install build-essential  # Debian, Ubuntu, Mint, etc.
   $ sudo yum group install "Development Tools"  # RedHat, CentOS
   

1. Install pyenv

   • If you're using homebrew or linuxbrew, follow the homebrew installation instructions
   • If you're not using homebrew, you probably should be
   • If you really insist on not using homebrew, follow the basic installation instructions

2. Install the latest stable version of Python:

   $ pyenv install 3.5.0
   Downloading Python-3.5.0.tgz...
   -> https://yyuu.github.io/pythons/584e3d5a02692ca52fce505e68ecd77248a6f2c99adf9db144a39087336b0fe0
   Installing Python-3.5.0...
   Installed Python-3.5.0 to ~/.pyenv/versions/3.5.0
   

3. Set your global Python installation:

   $ pyenv global 3.5.0
   

Windows

1. Download the installer from https://www.python.org/downloads/release/python-350/

   • 32 bit: https://www.python.org/ftp/python/3.5.0/python-3.5.0.exe
   • 64 bit: https://www.python.org/ftp/python/3.5.0/python-3.5.0-amd64.exe

2. Double click the installer to run it

Installing pip and creating your first virtual environment

All Platforms

0. Make sure python is in your path (usually not needed on OS X and Linux systems):

   C:\>set PATH=C:\Program Files\Python 3.5;%PATH%  # Windows
   C:\>set PYTHONPATH=%PYTHONPATH%;C:\My_python_lib  # Windows
   

1. Make sure you have pip:

   $ python -m ensurepip
   Ignoring indexes: https://pypi.python.org/simple
   Requirement already satisfied (use --upgrade to upgrade): setuptools in ~/.pyenv/versions/3.5.0/lib/python3.5/site-packages
   Requirement already satisfied (use --upgrade to upgrade): pip in ~/.pyenv/versions/3.5.0/lib/python3.5/site-packages
   

2. Create a virtual environment (homework: check out virtualenv and virtualenvwrapper):

   $ pyvenv venv
   

3. Activate your virtual environment:

   $ source venv
   

4. Install a package:

   $ python -m pip install requests
   Collecting requests
   Using cached requests-2.8.1-py2.py3-none-any.whl
   Installing collected packages: requests
   Successfully installed requests-2.8.1
   

5. Verify that everything's working properly:

   $ python
   Python 3.5.0 (default, Dec  1 2015, 19:42:21)
   [GCC 4.2.1 Compatible Apple LLVM 7.0.0 (clang-700.1.76)] on darwin
   Type "help", "copyright", "credits" or "license" for more information.
   >>> import requests
   >>> requests.__version__
   '2.8.1'
   

5. Embrace the Python philosophy:

   >>> import this