无法验证并插入到mongo DB中。pymongo- python

from pymongo import MongoClient

# 创建数据库连接
client = MongoClient('mongodb://localhost:27017/')

# 验证连接是否成功
print(client.list_database_names())

from pymongo import MongoClient

# 创建数据库连接
client = MongoClient('mongodb://localhost:27017/')

# 进行用户认证
db = client['admin']
db.authenticate('username', 'password')

from pymongo import MongoClient

# 创建数据库连接
client = MongoClient('mongodb://localhost:27017/')

# 选择数据库和集合
db = client['mydatabase']
collection = db['mycollection']

# 插入数据
data = {'name': 'John', 'age': 25}
collection.insert_one(data)