from pymongo import MongoClient

client = pymongo.MongoClient("mongodb+srv://<username>:<password>@cluster0.e4w3e80.mongodb.net/Cluster0?retryWrites=true&w=majority")
db = client.test

db = client.dbsparta

doc={
    'name':'bob',
    'age':27


}

db.user.insert_one(doc) 

pymongo.MongoClient() 괄호 안에 들어가는 부분이 잘못된것 같습니다

client = pymongo.MongoClient("mongodb+srv://<username>:<password>@cluster0.e4w3e80.mongodb.net/?retryWrites=true&w=majority")

db = client.test

db에서 복사한 코드는 이것입니다