How to join without loop

join_without_loop

from sqlalchemy import (create_engine, and_, Column, Integer, String,
                        ForeignKey, Float)
 
from sqlalchemy.orm import relationship, sessionmaker

from sqlalchemy.ext.declarative import declarative_base

import random
import pandas as pd

engine = create_engine('sqlite:///:memory:')
Base = declarative_base()


class Product(Base):

    __tablename__ = 'product'

    id = Column(Integer, primary_key=True)
    product_code = Column(Integer, index=True)
    name = Column(String(50))
    something = Column(String(50))


class Forecast(Base):

    __tablename__ = 'forecast'

    id = Column(Integer, primary_key=True)
    product_id =Column(Integer, ForeignKey('product.id'),
                       index=True)
    week_number = Column(Integer)
    forecast_qty = Column(Float)

    product = relationship(Product)


if __name__ == '__main__':

    Session = sessionmaker(bind=engine)
    session = Session()
    Base.metadata.create_all(engine)

    # Create a fake product
    prod = Product(product_code=1234,
                   name='Stag do in Vegas',
                   something="No, I'm not that guy")
    session.add(prod)
    session.commit()

    # Create fake forecast for the next 4 weeks
    for x in range(4):
        demand = random.randint(0, 100)
        forecast = Forecast(product_id=prod.id,
                            week_number=x,
                            forecast_qty=demand)
        session.add(forecast)
    session.commit()

    # NOW QUERY
    forecast = session.query(Forecast).join(Product).all()

    expanded = []
    for item in forecast: # <-- I want rid of this loop
        item_dict = item.__dict__
        product_name = item.product.name
        item_dict['product_name'] = product_name
        expanded.append(item_dict)

    df = pd.DataFrame(expanded)
    print(df.head())