Write a test without setup or tear-down:

def test_sleep():
    import time
    time.sleep(2)

Run pytest --durations 0 on this test. Observe something like

======================= slowest test durations =======================
2.00s call     tests/test.py::test_sleep
0.00s teardown tests/test.py::test_sleep
0.00s setup    tests/test.py::test_sleep

On medium-size testsuites, where one would like to see timings off all tests that run, these useless 0.00s entries clutter the output, so I'd suggest to remove them.

Versions

python-pytest 3.8.1-1
python 3.7.0-4
from archlinux repos