initial settings:
You need to create new db(postgreSQL) with following name or password: postgresql://postgres:123@localhost/book_shop
name: book_shop
pass: 123
or just change app.config['SQLALCHEMY_DATABASE_URI'] in app.py to your ones

to fill db:
from app import app
from app import db
db.create_all()
from initial_data_to_db import fill_db_with_data
fill_db_with_data()

to start app:
app.run()