引入内置模块bson中ObjectId,pymongo模块的的实现是基于bson模块。
mongo的每一条数据都有一个主键_id,类型为ObjectId。ObjectId是由24位16进制数构成，例如：ObjectId("5c643f1cf146b1b8785fc39f")
from bson import ObjectId
from pymongo import MongoClient
conn = pymongo.MongoClient('mongodb://root:abc123@127.0.0.1/admin'
str = "5sdfadsfasdfxzcasdfasdfas"
findinfo = conn.db_name.table_name.find({"_id" : ObjectId(str)})
