def METHOD_NAME(app: Flask):
    age = filters.age
    now = datetime.datetime(2012, 6, 10, 10, 10, 10, tzinfo=utc)
    d1m = datetime.datetime(2012, 6, 10, 10, 10, 0, tzinfo=utc)
    d3w = datetime.datetime(2012, 5, 18, 8, 0, 0, tzinfo=utc)
    d2011 = datetime.datetime(2011, 9, 4, 12, 12, 0, tzinfo=utc)
    # default parameters
    assert age(None) == ""
    assert age(d1m, now) == "1 minute ago"
    assert age(d3w, now) == "3 weeks ago"
    # with direction
    assert age(d1m, now, add_direction=False) == "1 minute"
    assert age(d3w, now, add_direction=False) == "3 weeks"
    # with date_threshold
    assert age(d1m, now, date_threshold="day") == "1 minute ago"
    # same year: 2012 not shown
    assert age(d3w, now, date_threshold="day") == "May 18, 4:00 PM"
    # different year: 2011 shown
    assert age(d2011, now, date_threshold="day") == "September 4, 2011, 8:12 PM"
    # using default parameter now=None
    # dt_patcher = mock.patch.object(
    #     datetime, "datetime", mock.Mock(wraps=datetime.datetime)
    # )
    # with dt_patcher as mocked:
    #     mocked.utcnow.return_value = now
    #     assert age(d1m) == "1 minute ago"