When installing flask and phytml, I get the error message: "The term 'pip3' is not recognized..." How do I fix this?
* Windows: <a class="notion-link-token notion-enable-hover" href="https://www.liquidweb.com/kb/install-pip-windows/" rel="noopener noreferrer" target="_blank">https://www.liquidweb.com/kb/install-pip-windows/</a>
* Mac: <a class="notion-link-token notion-enable-hover" href="https://www.geeksforgeeks.org/how-to-install-pip-in-macos/" target="_blank">https://www.geeksforgeeks.org/how-to-install-pip-in-macos/</a>