Python操作MongoDB查询时处理ObjectId

从bson中导入objectid对象，将字符串转换成id对象查询使用：

from bson import objectid
import pymongo
conn = pymongo.mongoclient('mongodb://root:abc123@127.0.0.1/admin'
str = "5sdfadsfasdfxzcasdfasdfas"
findinfo = conn.db_name.table_name.find({"_id" : objectid(str)})