从cursor.fetchone()中获取字典中的flask mysql SUM()小数

from flask import Flask
from flask_mysqldb import MySQL

app = Flask(__name__)
app.config['MYSQL_HOST'] = 'localhost'
app.config['MYSQL_USER'] = 'username'
app.config['MYSQL_PASSWORD'] = 'password'
app.config['MYSQL_DB'] = 'database_name'

mysql = MySQL(app)

@app.route('/')
def get_sum():
    cursor = mysql.connection.cursor()
    cursor.execute("SELECT SUM(column_name) FROM table_name")
    result = cursor.fetchone()
    sum_value = result[0]
    # 如果需要处理小数，可以使用DECIMAL函数将结果转换为小数类型
    # cursor.execute("SELECT DECIMAL(SUM(column_name), 2) FROM table_name")
    # result = cursor.fetchone()
    # sum_value = result[0]
    return str(sum_value)

if __name__ == '__main__':
    app.run()