Is it possible to use argparse to capture an arbitrary set of optional arguments?

Question

Is it possible to use argparse to capture an arbitrary set of optional arguments?

For example both the following should be accepted as inputs:

Answer 1

This is kind of a hackish way, but it works well:

Check, which arguments are not added and add them

import argparse
parser = argparse.ArgumentParser()
parser.add_argument("foo")
parser.add_argument("-bar", type=int)
# parser can have any arguments, whatever you want!

parsed, unknown = parser.parse_known_args() # this is an 'internal' method
# which returns 'parsed', the same as what parse_args() would return
# and 'unknown', the remainder of that
# the difference to parse_args() is that it does not exit when it finds redundant arguments

for arg in unknown:
    if arg.startswith(("-", "--")):
        # you can pass any arguments to add_argument
        parser.add_argument(arg, type=, ...)

args = parser.parse_args()

For example:

python3 arbitrary_parser.py ha -bar 12 -extra1 value1 -extra2 value2

Then the result would be

args = Namespace(bar=12, foo='ha', extra1='value1' extra2='value2')