python重复连接mysql数据库

import mysql.connector

def fetch_data():
    conn = mysql.connector.connect(user='user', password='password', host='host', database='database')
    cursor = conn.cursor()
    cursor.execute("SELECT * FROM table")
    result = cursor.fetchall()
    cursor.close()
    conn.close()
    return result

from mysql.connector.pooling import MySQLConnectionPool

pool = MySQLConnectionPool(pool_name="mypool", pool_size=5, user='user', password='password', host='host', database='database')

def fetch_data():
    conn = pool.get_connection()
    cursor = conn.cursor()
    cursor.execute("SELECT * FROM table")
    result = cursor.fetchall()
    cursor.close()
    conn.close()  # 连接会返回到连接池而不是真正关闭
    return result

def fetch_data_with_context():
    with pool.get_connection() as conn:
        with conn.cursor() as cursor:
            cursor.execute("SELECT * FROM table")
            result = cursor.fetchall()
    return result