text: from app import db
  
  
  class User(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))
      token = db.Column(db.String(12), index=True, unique=True)
      iv_string = db.Column(db.String(16))
      encryption_key = db.Column(db.String(12))
  
      def __repr__(self):
          return '<User {}>'.format(self.username)
  
  
  class Vault(db.Model):
      id = db.Column(db.Integer, primary_key=True)
      last_four = db.Column(db.Integer)
      card_token = db.Column(db.String(128))
      user_id = db.Column(db.Integer, db.ForeignKey('user.id'))
      uuid = db.Column(db.String(128), index=True, unique=True)
  