note on python versions note on python versions many operating systemsincluding macos and linuxcome with python preinstalled the version of python that comes with your operating system is called the system python the system python is used by your operating system and is usually out of date it' essential that you have the most recent version of python so that you can successfully follow along with the examples in this book important do not attempt to uninstall the system pythonyou can have multiple versions of python installed on your computer in this you'll install the latest version of python alongside any system python that may already exist on your machine note even if you already have python installedit' still good idea to skim this to double-check that your environment is set up for following along with this book this is split into three sectionswindowsmacosand ubuntu linux find the section for your operating system and follow the steps to get set upthen skip ahead to the next if you have different operating systemthen check out real python' "python installation setup guideto see if your os is covered readers on tablets and mobile devices can refer to the "online python interpreterssection for some browser-based options