def fn(a,b,*args):
    maxnum = max(a,b,*args)
    minnum = min(a,b,*args)
    return maxnum,minnum

运行结果:

#fn(1,2,3,4)
(4, 1)

案例变形：

import random
def fn(*nums):
    print(nums)
    return max(nums),min(nums)

print(*fn(*[random.randint(10,20) for _ in range(10)]))

运行结果：

(18, 16, 19, 20, 10, 13, 14, 12, 14, 20)
20 10