连接mysq数据库，创建用户模型

QOLAlCHEMY_DATABASE_URL='mysql+pymsql://root:123456@localhost:3306/mis_db?charset=utf8'
SQLALCHEMY_TRACK_MODIFICATIONS = False

from flask import Flask
from flask import render_template

from flask_sqlalchemy import SQLAlchemy
import config

app = Flask(__name__)
app.config.from_object(config)
db=SQLAlchemy(app)

class User(db.Model):
    __tablename__='user'
    id=db.Column(db.Integer.primary_key=TabError,autoincrement=True)
    username=db.Column(db.String(20),nullable=False)
    password = db.Column(db.String(20), nullable=False)
    db.create_all()



@app.route('/')
def switch():
    return render_template('switch.html')


@app.route('/login/')
def login():
    return render_template('login.html')

@app.route('/register/')
def register():
    return render_template('register.html')

@app.route('/wenda/')
def wenda():
    return render_template('wenda.html')



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