import argparse
import typing

Seconds = typing.NewType("Seconds", float)
Minutes = typing.NewType("Minutes", float)

class TimeNamespace(argparse.Namespace):
    time: Seconds

def sec_to_min(s: Seconds) -> Minutes:
    return Minutes(s / 60)

parser = argparse.ArgumentParser()
parser.add_argument("-t", "--time", default=1., type=float,
                    help="time in seconds")
args = parser.parse_args(namespace=TimeNamespace())

try:
    # mypy reveals type "__main__.Seconds"
    reveal_type(args.time)
except NameError:
    pass

seconds: Seconds = args.time
print(sec_to_min(args.time))