Specifying default filenames with argparse, but not opening them on --help?

Question

Let\'s say I have a script that does some work on a file. It takes this file\'s name on the command line, but if it\'s not provided, it defaults to a known filename (conte

Answer 1

Use stdin as default:

parser.add_argument('file', default='-', nargs='?', type=argparse.FileType('r'))