text: from edu_web_app import db, app, login
  from datetime import datetime
  from werkzeug.security import generate_password_hash, check_password_hash
  from flask_login import UserMixin
  from time import time
  import jwt
  
  class User(UserMixin, db.Model):
      id = db.Column(db.Integer, primary_key=True)
      username = db.Column(db.String(64), index=True, unique=True)
      email = db.Column(db.String(120), index=True, unique=True)
      password_hash = db.Column(db.String(128))
  
      def set_password(self, password):
          self.password_hash = generate_password_hash(password)
  
      def check_password(self, password):
          return check_password_hash(self.password_hash, password)
  
      def __repr__(self):
          return '<User {}>'.format(self.username)
  
      def get_reset_password_token(self, expires_in=2400):
          return jwt.encode(
              {'reset_password': self.id, 'exp': time() + expires_in}, 
              app.config['SECRET_KEY'], algorithm= 'HS256').decode('utf-8')
  
      @staticmethod
      def verify_reset_password_token(token):
          try:
              id = jwt.decode(token, app.config['SECRET_KEY'],
                  algorithms=['HS256'])['reset_password']
          except:
              return
          return User.query.get(id)
  
  
  
  class OER(db.Model):
      id = db.Column(db.Integer, primary_key=True)
      body = db.Column(db.String(1500))
      timestamp = db.Column(db.DateTime, index=True, default=datetime.utcnow)
      user_id = db.Column(db.Integer, db.ForeignKey('user.id'))
  
      def __repr__(self):
          return '<OER {}>'.format(self.body)
          
  
  @login.user_loader
  def load_user(id):
      return User.query.get(int(id))