python for-else语句

这里来直接看一个例子，找出​

​0-50​

​内的所有质数并打印。

# -*- coding:utf-8 -*-

def findPrimeNumber():
    for n in range(2, 30):
        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')


if __name__ == '__main__':
    findPrimeNumber()