Integer range command-line arguments in Python

IntRangeArg.py

import argparse


class IntRangeArg:
    def __init__(self, start=None, stop=None):
        assert start is None or stop is None or start < stop
        self.start = start
        self.stop = stop

    def __contains__(self, value):
        return (self.start is None or value >= self.start) and (self.stop is None or value < self.stop)

    def __call__(self, arg):
        value = None
        try:
            value = int(arg)
        except ValueError:
            pass
        if value is None or value not in self:
            raise argparse.ArgumentTypeError(f"invalid int value: '{arg}' (choose from [{self.start}, {self.stop}))")
        return value