Python函数编写

#编写函数，实现如下组合计算公式：C(m, n) = m!/n! /(m - n)!

代码如下，如有帮助，请记得采纳，谢谢

def cal(m, n):
    ret_m = 1
    for i in range(1, m+1):
        ret_m *= i
    ret_n = 1
    for i in range(1, m+1):
        ret_n *= i
    ret_mn = 1
    for i in range(1, m-n):
        ret_mn *= i
    ret = ret_m/ret_n/ret_mn
    print(ret)
    return ret