[Python] argparse's "required" ignored in the help screen?

Consider the following code:

import argparse
parser = argparse.ArgumentParser()
parser.add_argument('-o', required=True, nargs=1)
parser.parse_args(['-h'])


Why am I getting the following output even if I said that -o is required?

usage: test.py [-h] -o O

optional arguments:
-h, --help show this help message and exit
-o O


I would expect the help text to say that -o is required.

Continue reading...