Flask将应用程序配置导入到model.py

Question

我需要将我的 app 导入烧瓶而不是其他模块models.py，因为我想将我的对象类与Web导航逻辑分开。

我遵循此post，但是很遗憾，我无法导入User为什么我不太了解：（。

application.py脚本：

from flask import *
from flask_login import LoginManager
from md_dbactions import User

dblocation = 'sqlite:///path'

app = Flask(__name__)
login_manager = LoginManager()
login_manager.init_app(app)
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False
app.config['SQLALCHEMY_DATABASE_URI'] = dblocation

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. My code

脚本md_dbactions.py（模型）：

import sqlite3
from flask_sqlalchemy import SQLAlchemy    
from sqlalchemy import Column, Integer, String
from sqlalchemy import create_engine
from application import app # from my application.py


db = SQLAlchemy(app)


class User(db.Model):
    __tablename__ = 'tbl_user'
    id = Column(Integer, primary_key=True)
    name = Column(String(50), unique=True)
    email = Column(String(200), unique=True)
    grade = Column(String(50), unique=True)
    category = Column(String(50), unique=True)
    username = Column(String(50), unique=True)
    password = Column(String(50), unique=True)

    def __init__(self, name=None, email=None,grade=None,
                 category=None,username=None,password=None):
        self.name = name
        self.email = email
        self.grade = grade
        self.category = category
        self.username = username
        self.password = password

    def __repr__(self):
        record = '{},{},{},{},{},{},{}'.format(self.id,self.name,self.email,
        self.grade,self.category,self.username,self.password)
        return record

那我的错误是：