old_contents: import os
  import sys
  from sqlalchemy import Column, ForeignKey, Integer, String
  from sqlalchemy.ext.declarative import declarative_base
  from sqlalchemy.orm import relationship
  from sqlalchemy import create_engine
  
  Base = declarative_base()
  
  
  class Category(Base):
      __tablename__ = 'category'
  
      id = Column(Integer, primary_key=True)
      name = Column(String(250), nullable=False)
  
      @property
      def serialize(self):
          """Return object data in easily serializeable format"""
          return {
              'name': self.name,
              'id': self.id
          }
  
  
  class CategoryItem(Base):
      __tablename__ = 'category_item'
  
      name = Column(String(80), nullable=False)
      id = Column(Integer, primary_key=True)
      description = Column(String(250))
      category_id = Column(Integer, ForeignKey('category.id'))
      category = relationship(Category)
  
      @property
      def serialize(self):
          """Return object data in easily serializeable format"""
          return {
              'name': self.name,
              'description': self.description,
              'id': self.id
          }
  
  
  engine = create_engine('sqlite:///catalog.db')
  
  
  Base.metadata.create_all(engine)
  
new_contents: import os
  import sys
  from sqlalchemy import Column, ForeignKey, Integer, String
  from sqlalchemy.ext.declarative import declarative_base
  from sqlalchemy.orm import relationship
  from sqlalchemy import create_engine
  
  Base = declarative_base()
  
  
  class User(Base):
      __tablename__ = 'user'
  
      id = Column(Integer, primary_key=True)
      name = Column(String(250), nullable=False)
      email = Column(String(250), nullable=False)
      picture = Column(String(250))
  
  class Category(Base):
      __tablename__ = 'category'
  
      id = Column(Integer, primary_key=True)
      name = Column(String(250), nullable=False)
      user_id = Column(Integer, ForeignKey('user.id'))
      user = relationship(User)
  
      @property
      def serialize(self):
          """Return object data in easily serializeable format"""
          return {
              'name': self.name,
              'id': self.id
          }
  
  
  class CategoryItem(Base):
      __tablename__ = 'category_item'
  
      name = Column(String(80), nullable=False)
      id = Column(Integer, primary_key=True)
      description = Column(String(250))
      category_id = Column(Integer, ForeignKey('category.id'))
      category = relationship(Category)
      user_id = Column(Integer, ForeignKey('user.id'))
      user = relationship(User)
  
      @property
      def serialize(self):
          """Return object data in easily serializeable format"""
          return {
              'name': self.name,
              'description': self.description,
              'id': self.id
          }
  
  
  engine = create_engine('sqlite:///catalog.db')
  
  
  Base.metadata.create_all(engine)
  
subject: Add user table