I seem to have deleted some code for programming tests, how do I revert to the default?

Course Q&A Deep Learning Specialization Improving Deep Neural Networks: Hyperparameter tun
1

I seem to have deleted some of the code for programming tests in the course2 week3 programming job, how do I revert to the default?
help~~~~~~~~~~~~

2

I think Paul provided an excellent guidance at here FAQ: Frequently Asked Questions for all DLS Courses