Cannot complete lab due to it using deprecated python runtime

Here is the lab: https://www.cloudskillsboost.google/course_sessions/11740698/labs/456666

For Task 2... deploying to app engine. We are instructed to add runtime: python37. When deploying, there is an error that python 37 is no longer supported. I tried to change it to python38 and deploy... which worked. Although the "Check My Progress" feature failed so I cannot successfully complete the lab.