How to use the threadpoolctl._ALL_USER_APIS function in threadpoolctl

def _threadpool_info():
    # Like threadpool_info but return the object instead of the list of dicts
    return _ThreadpoolInfo(user_api=_ALL_USER_APIS)

def test_threadpool_limits_bad_input():
    # Check that appropriate errors are raised for invalid arguments
    match = re.escape("user_api must be either in {} or None."
                      .format(_ALL_USER_APIS))
    with pytest.raises(ValueError, match=match):
        threadpool_limits(limits=1, user_api="wrong")

    with pytest.raises(TypeError,
                       match="limits must either be an int, a list or a dict"):
        threadpool_limits(limits=(1, 2, 3))

def test_set_threadpool_limits_by_api(user_api, limit):
    # Check that the maximum number of threads can be set by user_api
    original_info = _threadpool_info()

    modules_matching_api = original_info.get_modules("user_api", user_api)
    if not modules_matching_api:
        user_apis = _ALL_USER_APIS if user_api is None else [user_api]
        pytest.skip("Requires a library which api is in {}".format(user_apis))

    with threadpool_limits(limits=limit, user_api=user_api):
        for module in modules_matching_api:
            if is_old_openblas(module):
                continue
            # threadpool_limits only sets an upper bound on the number of
            # threads.
            assert 0 < module.get_num_threads() <= limit

    assert _threadpool_info() == original_info