在python(flask)中添加第二个MySQL连接

from flask import Flask
from flask_sqlalchemy import SQLAlchemy

app = Flask(__name__)

app.config['SQLALCHEMY_DATABASE_URI'] = 'mysql://username:password@host/database'

db = SQLAlchemy(app)

class User(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    username = db.Column(db.String(80), unique=True)
    email = db.Column(db.String(120), unique=True)

    def __init__(self, username, email):
        self.username = username
        self.email = email

app.config['SQLALCHEMY_BINDS'] = {
    'second_db': 'mysql://username:password@host/second_database'
}

db.init_app(app)

class Product(db.Model):
    __bind_key__ = 'second_db'
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(80), unique=True)
    price = db.Column(db.Float)

    def __init__(self, name, price):
        self.name = name
        self.price = price