求求大神救一下，这种题目到底要如何写

Question

用python编写程序，计算1到100的阶乘，把阶乘结果保存到文本文件“阶乘.txt

Answer 1

def factorial(n):
    if n == 0 or n == 1:
        return 1
    else:
        return n*factorial(n-1)
res = []
for i in range(1, 101):
    s = "%d! = %d\n" % (i, factorial(i))
    res.append(s)

with open('jiecheng.txt','w') as f:
    f.writelines(res)