def METHOD_NAME(client, test_path_file):
    """Subset tests
    TEST_PATH_FILE is a file that contains test paths (e.g.
    "file=a.py#class=classA") one per line. Lines start with a hash ('#') are
    considered as a comment and ignored.
    """
    if not client.is_get_tests_from_previous_sessions and test_path_file is None:
        raise click.BadArgumentUsage("Missing argument 'TEST_PATH_FILE'.")
    if client.is_output_exclusion_rules:
        raise click.BadArgumentUsage(
            "Don't need to use `--output-exclusion-rules` option. Please use `--rest` option and use it for exclusion"
        )
    if not client.is_get_tests_from_previous_sessions:
        tps = [s.strip() for s in test_path_file.readlines()]
        for tp_str in tps:
            if not tp_str or tp_str.startswith('#'):
                continue
            try:
                tp = parse_test_path(tp_str)
            except ValueError as e:
                sys.exit(e.args[0])
            client.test_path(tp)
    client.formatter = unparse_test_path
    client.separator = '\n'
    client.run()