python 时间格式化

2018-10-25 17:49:51 监控软件 原始
2018-10-2517:49:51 切割后
2018/10/25 17:49:51 格式化后
shijian = ' '.join(response.xpath('//html/body/div/div/div/div/div/a[4]/text()').extract())
        print(shijian,'原始')
        if  '2018' != shijian.split('-',1)[0]:
            shijian = '暂无'
            print(shijian,'暂无')
        else:
            shijian_time = ''.join(shijian.split(' ')[:2])
            shijian_me = datetime.strptime(shijian_time,'%Y-%m-%d%H:%M:%S').strftime('%Y/%m/%d %H:%M:%S')
            print(shijian_time,'切割后')
            print(shijian_me,'格式化后')