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Make sure to select the option to add python.exe to PATH. If you do not do this the first time you run through, there are many ways to fix this listed below.
https://github.com/waterloo-rocketry/software-onboarding/tree/Python-Setup-Tutorial/Python-Tutorial
https://www.educative.io/answers/how-to-add-python-to-the-path-variable-in-mac
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