# coding: utf-8 import functools def my_default_by_or(func): @functools.wraps(func) def wrapper(*args): args = dict(enumerate(args)) args = [args.get(i) or v for i, v in enumerate(func.__defaults__)] return func(*args) return wrapper @my_default_by_or def unpack_with_default(a=1, b=2, c=3, d=4, e=5): return a, b, c, d, e out = unpack_with_default(1, 0, 2) print(out)