Python Setup

Perform the following to install/configure Python & package management tools.

Note

All commands below are to be run as your user. (i.e. not root/sudo/Administrator).

  1. Ensure you have a working python environment:
    • On macOS:
      • Note: Substitute .bash_profile in place of .zshrc below if using Bash (e.g. macOS pre-Catalina)

      • Add local python bin directories to $PATH:

        PYTHONVER=$(python3 -c "import sys;print(str(sys.version_info.major)+'.'+str(sys.version_info.minor))")
        if ! grep -s '\.local\/bin' ~/.zshrc > /dev/null 2>&1 || ! grep -s "Library\/Python\/$PYTHONVER/bin" ~/.zshrc > /dev/null 2>&1 ; then echo "export PATH=\"\$HOME/Library/Python/$PYTHONVER/bin:\$HOME/.local/bin:\$PATH\"" >> ~/.zshrc; fi
        
      • Run source ~/.zshrc to use the updated PATH.

    • On Windows:
      • Install Python (choose the latest Windows x86-64 executable installer and run it):
        • On the initial setup page, click Customize installation

        • Leave all Optional Features selected, and click Next

        • On the Advanced Options page change the following options and click Install:
          • Check the Install for all users and Add Python to environment variables options.

          • Change the install location to C:\Python37 (updating Python37 to the appropriate directory for the installed version, e.g. Python38 for Python 3.8)

        • At the Setup was successful screen, click Disable path length limit and then close the setup program.

      • Edit the Path environment variable for your user:
        • In the Start Menu, start typing environment variables and select Edit environment variables for your account.

        • In the User variables for your username, select Path and click Edit...

        • Append %USERPROFILE%\AppData\Roaming\Python\Python37\Scripts & %USERPROFILE%\.local\bin to the current Variable values and click Ok
          • Change Python37 to the appropriate directory for the installed version (e.g. Python38 for Python 3.8)

          • In Windows Server 2016, the value is shown in a single line – add it with semicolons:

            %USERPROFILE%\AppData\Roaming\Python\Python37\Scripts;%USERPROFILE%\.local\bin;
            
        • Click Ok to close the Environment Variables window.

        • Close all existing PowerShell windows and launch a new one to use the updated PATH.

    • On Ubuntu Linux:
      • Add local python bin directory to $PATH:

        if ! grep 'HOME\/\.local\/bin' ~/.bash_profile > /dev/null 2>&1; then echo 'export PATH=$HOME/.local/bin:$PATH' >> ~/.bash_profile; fi
        
      • Run source ~/.bash_profile to use the updated PATH.

      • Install Python 3 and dependencies:

        sudo apt -y install python3-pip
        
  2. Install python package managers:

    pip3 install --user pipenv pipx
    

Package Installation

Afterwards, your user will be able to install additional Python packages using one of the following tools. Each wraps the base pip package manager and automatically manages virtual environments to ensure package dependencies don’t conflict.

pipx

Global CLIs & utilities, like the AWS CLI, can be installed via pipx:

pipx install awscli

pipenv

Utilities used in a project should generally have their versions stored in the project repository, so users (now and in the future) and remote build systems use the same versions specified in the repo.

pipenv works similarly to pipx, but creates a lockfile that can be checked into a repo:

pipenv install runway