How to use the pglast._remove_stmt_len_and_location function in pglast

def roundtrip(sql):
    orig_ast = parse_sql(sql)
    _remove_stmt_len_and_location(orig_ast)

    serialized = RawStream()(Node(orig_ast))
    try:
        serialized_ast = parse_sql(serialized)
    except:  # noqa
        raise RuntimeError("Could not reparse %r" % serialized)
    _remove_stmt_len_and_location(serialized_ast)
    assert orig_ast == serialized_ast, "%r != %r" % (sql, serialized)

    indented = IndentedStream()(Node(orig_ast))
    try:
        indented_ast = parse_sql(indented)
    except:  # noqa
        raise RuntimeError("Could not reparse %r" % indented)
    _remove_stmt_len_and_location(indented_ast)
    assert orig_ast == indented_ast, "%r != %r" % (sql, indented)

_remove_stmt_len_and_location(orig_ast)

    serialized = RawStream()(Node(orig_ast))
    try:
        serialized_ast = parse_sql(serialized)
    except:  # noqa
        raise RuntimeError("Could not reparse %r" % serialized)
    _remove_stmt_len_and_location(serialized_ast)
    assert orig_ast == serialized_ast, "%r != %r" % (sql, serialized)

    indented = IndentedStream()(Node(orig_ast))
    try:
        indented_ast = parse_sql(indented)
    except:  # noqa
        raise RuntimeError("Could not reparse %r" % indented)
    _remove_stmt_len_and_location(indented_ast)
    assert orig_ast == indented_ast, "%r != %r" % (sql, indented)

    # Run ``pytest -s tests/`` to see the following output
    print()
    print(indented)

def roundtrip(sql):
    orig_ast = parse_sql(sql)
    _remove_stmt_len_and_location(orig_ast)

    serialized = RawStream()(Node(orig_ast))
    try:
        serialized_ast = parse_sql(serialized)
    except:  # noqa
        raise RuntimeError("Could not reparse %r" % serialized)
    _remove_stmt_len_and_location(serialized_ast)
    assert orig_ast == serialized_ast, "%r != %r" % (sql, serialized)

    indented = IndentedStream()(Node(orig_ast))
    try:
        indented_ast = parse_sql(indented)
    except:  # noqa
        raise RuntimeError("Could not reparse %r" % indented)
    _remove_stmt_len_and_location(indented_ast)
    assert orig_ast == indented_ast, "%r != %r" % (sql, indented)

    # Run ``pytest -s tests/`` to see the following output
    print()
    print(indented)

def workhorse(args):
    input = args.infile or sys.stdin
    with input:
        statement = input.read()

    if args.parse_tree or args.plpgsql:
        tree = parse_plpgsql(statement) if args.plpgsql else parse_sql(statement)
        if args.no_location:
            _remove_stmt_len_and_location(tree)
        output = args.outfile or sys.stdout
        with output:
            json.dump(tree, output, sort_keys=True, indent=2)
            output.write('\n')
    else:
        try:
            prettified = prettify(
                statement,
                compact_lists_margin=args.compact_lists_margin,
                split_string_literals_threshold=args.split_string_literals,
                special_functions=args.special_functions,
                comma_at_eoln=args.comma_at_eoln,
                semicolon_after_last_statement=args.semicolon_after_last_statement)
        except Error as e:
            print()
            raise SystemExit(e)