db.py

from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy import *
base= declarative_base()

class Item_information(base):
	__tablename__= 'cpanel_item_information'

	id= Column(Integer, primary_key= True)
	name= Column(String(255))
	description= Column(Text)
	slug= Column(String(255))
	weight= Column(Integer)
	cost= Column(Integer)
	category= Column(String(255))
	model= Column(String(255))

class Item(base):
	__tablename__= 'rp_items'

	steamid= Column(Text, primary_key= True, autoincrement= False)
	item_id= Column(Text, primary_key= True, autoincrement= False)
	item_quantity= Column(Text)

main.py

from sqlalchemy import *
from sqlalchemy.orm import sessionmaker

import db

def Start_session():
	engine = create_engine(db_url)
	Session = sessionmaker(bind=engine)
	return Session()

session = Start_session()

info= aliased(db.Item_information)
items= session.query(db.Item).join(info, db.Item.item_id==info.slug).all()