def test_simple():
num_list = [1, 2]
observed = mean(num_list)
expected = 1.5
assert observed == expected, 'My test failed'
def test_many(num_list, expected_mean):
assert mean(num_list) == expected_mean
def test_empty():
with pytest.raises(ZeroDivisionError):
mean([])
def test_type_error():
with pytest.raises(TypeError):
mean(['a', 'b', 'c', 'd'])
def test_more(num_list):
assert mean(num_list) == 3.0