def METHOD_NAME() -> None:
    assert dtutil.display_time(121, granularity=1) == '2 minutes'
    assert dtutil.display_time(121, granularity=2) == '2 minutes, 1 second'
    assert dtutil.display_time(121, granularity=3) == '2 minutes, 1 second'
    assert dtutil.display_time(159, granularity=1) == '3 minutes'
    assert dtutil.display_time(91, granularity=1) == '2 minutes'
    assert dtutil.display_time(6900, granularity=2) == '1 hour, 55 minutes'
    assert dtutil.display_time(345610, granularity=4) == '4 days, 10 seconds'
    assert dtutil.display_time(4860) == '1 hour, 21 minutes'
    assert dtutil.display_time(86400) == '1 day'
    assert dtutil.display_time(0, 2) == 'now'