Inspired by jane street engineering blog # python poc First write a test like ```python import expect from expect_test def test_fib(): result = fib(15) expect(result, None) ``` Then, run with EXPECT_TEST=1 will replace the 2nd argument with the evaluated value of the 1st argument. Running with EXPECT_TEST=0 will assert that the result equals the 2nd argument https://approvaltestscpp.readthedocs.io/en/latest/generated_docs/usinggoogletests.html https://pypi.org/project/expecttest/