python mongodb pymongo 连接 身份认证

参考： http://api.mongodb.com/python/current/examples/authentication.html

## 第一种
mongodb = pymongo.MongoClient(f'mongodb://{username}:{password}@localhost:27017/{databasename}', serverSelectionTimeoutMS=3000)


## 第二种
client_one = pymongo.MongoClient(ip,int(port),username=username,password=password,serverSelectionTimeoutMS=3000)