如何编写一次重命名多个列的函数？

import psycopg2

def rename_columns(table_name, column_mapping):
    # 连接到数据库
    conn = psycopg2.connect(database="your_database", user="your_user", password="your_password", host="your_host", port="your_port")
    cursor = conn.cursor()

    try:
        # 循环遍历列映射关系
        for old_column_name, new_column_name in column_mapping.items():
            # 构建SQL语句
            sql = f"ALTER TABLE {table_name} RENAME COLUMN {old_column_name} TO {new_column_name}"
            # 执行SQL语句
            cursor.execute(sql)

        # 提交事务
        conn.commit()
        print("Columns renamed successfully!")
    except Exception as e:
        # 发生错误时回滚事务
        conn.rollback()
        print("Error occurred:", str(e))
    finally:
        # 关闭数据库连接
        cursor.close()
        conn.close()

# 定义列映射关系
column_mapping = {
    "old_column1": "new_column1",
    "old_column2": "new_column2",
    "old_column3": "new_column3"
}

# 调用函数进行重命名
rename_columns("your_table", column_mapping)