python redis 批量设置过期key过程解析

from redis import Redis
def setExpiredKeys():
  try:
    if redis_pass == 'none':
      redisclient = Redis(host=redis_host, port=redis_port,db=0)
    else:
      redisclient = Redis(host=redis_host, port=redis_port, password=redis_pass)
    for key in redisclient.scan_iter(count=500):
      keyttl = redisclient.execute_command('ttl', key)
      if keyttl == -1: # 此处扫到key，可以进行导出处理或者执行命令
        redisclient.expire(key, 86400)
  except Exception as e:
    raise e
if __name__ == '__main__':
  redis_host = '192.168.0.1'
  redis_port = 6379
  redis_pass = '123456'
  setExpiredKeys()