docker 启动 postgres 15 设置密码为：zR6c49Mmmf4Rc6Vk请帮我写出docker-compose 配置。并使用python 测试连接 postgres 数据库和在容器内测试是否能连接postgres

version: '3.9'

services: db: image: postgres:15 restart: always environment: POSTGRES_PASSWORD: zR6c49Mmmf4Rc6Vk ports: - "5432:5432"

在python中测试连接postgres数据库：

import psycopg2

try:
    connection = psycopg2.connect(user="postgres",
                                  password="zR6c49Mmmf4Rc6Vk",
                                  host="localhost",
                                  port="5432",
                                  database="postgres")
    cursor = connection.cursor()
    print(connection.get_dsn_parameters(), "\n")

    cursor.execute("SELECT version();")
    record = cursor.fetchone()
    print("You are connected to - ", record, "\n")

except (Exception, psycopg2.Error) as error:
    print("Error while connecting to PostgreSQL", error)

finally:
    if connection:
        cursor.close()
        connection.close()
        print("PostgreSQL connection is closed")

在docker容器中测试连接postgres数据库：

docker exec -it <container_name> bash
psql -U postgres -h localhost

如果出现如下提示，证明连接成功：

Password for user postgres: 
psql (15.0 (Debian 15.0-1.pgdg110+1))
Type "help" for help.

postgres=#