Create a new branch for your coding exercise.
Make sure to create the following files in each exercise directory:
README.md: a description of the problem for students to read.exercise.py: the solution of the problem.tests.py: the tests that will check the problem has been solved correctly. Make sure to check as many edge cases as possible!student.py: the starting code we'll provide the students. You can add comments here and any required code.__init__.py: required so the test runner will be able to run these tests automatically.
Then, make a PR into master!