new_contents: 
  from flask_sqlalchemy import SQLAlchemy
  from sqlalchemy.orm import relationship
  from itsdangerous import (TimedJSONWebSignatureSerializer as Serializer, BadSignature, SignatureExpired)
  from passlib.apps import custom_app_context as pwd_context
  
  from .config import Config
  
  db = SQLAlchemy() #this is the creation of a sqlalchemy database instance
  
  class UserModel(db.Model):
  	""" This class represents the model of a user"""
  	__tablename__ = 'user'
  	id = db.Column(db.Integer, primary_key = True)
  	email = db.Column(db.String(250), nullable=False)
  	password = db.Column(db.String(250), nullable=False)
  
  	def __init__(self, email, password):
  		""" This method initializes the Usermodel with a password and an email """
  		self.email = email
  		self.password = pwd_context.encrypt(password)
  	
  	def verify_password(self, password):
  		""" This method verifies a password during login"""
  		return pwd_context.verify(password, self.password)
  
  	def generate_auth_token(self, expiration = 3600):
  		""" This method generates the token after a user is successfully logged in"""
  		s = Serializer(Config.SECRET_KEY, expires_in = expiration)
  		return s.dumps({ 'id': self.id })
  
  	@staticmethod
  	def verify_auth_token(token):
  		""" This method verifies a token when a request that requires authentication is made"""
  		s = Serializer(Config.SECRET_KEY)
  		try:
  			data = s.loads(token)
  		except SignatureExpired:
  			return None # valid token, but expired
  		except BadSignature:
  			return None # invalid token
  		user = UserModel.query.get(data['id'])
  		return user
  
  class BucketListModel(db.Model):
  	""" This class represents the model of a bucket list """
  	__tablename__ = 'bucketlist'
  	id = db.Column(db.Integer, primary_key = True)
  	name = db.Column(db.String(250), nullable=False)
  	date_created = db.Column(db.DateTime, default=db.func.current_timestamp())
  	date_modified = db.Column(db.DateTime, default=db.func.current_timestamp(),onupdate=db.func.current_timestamp())
  	created_by = db.Column(db.String(250), nullable=False)
  	items = relationship("ItemsModel", back_populates="bucketlist")
  	
  class ItemsModel(db.Model):
  	""" This class represents the model of a single item """
  	__tablename__ = 'items'
  	id = db.Column(db.Integer, primary_key = True)
  	name = db.Column(db.String(250), nullable=False)
  	date_created = db.Column(db.DateTime, default=db.func.current_timestamp())
  	date_modified = db.Column(db.DateTime, default=db.func.current_timestamp(),onupdate=db.func.current_timestamp())
  	done = db.Column(db.Boolean, default=True)
  	bucketlist_id = db.Column(db.Integer, db.ForeignKey('bucketlist.id'))
  	bucketlist = relationship("BucketListModel", back_populates="items")
  	
  
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