In this appendix we'll focus on pip as it is officially blessed by the core Python developers and comes with support out of the box. Although pip is not distributed with Python, a tool to install pip called ensurepip is included. It was done this way to allow pip to evolve at a different rate to the Python language and standard library.
It shouldn't usually be necessary to install pip with recent Python releases, as ensurepip is invoked automatically when Python is installed or when a new virtual environment is created. If for some reason you need to install pip manually, you can simply issue this command:
$ python -m ensurepip
The ensurepip module will do the rest. Bear in mind though, that pip will be installed into the environment corresponding to the python interpreter you invoke in this call.