4. 其他流程控制工具 — Python 3.10.2 文档

4.4 循环中的break、continue else

for n in range(2,10):
    for x in range(2,n):
        if n % x == 0 :
            print(n,'equals',x,'*',n//x)
            break
        else:
            #loop fell through without finding a factor
            print(n,'is a prime number')