db_migrate.py

from flask import Flask
from flask_sqlalchemy import SQLAlchemy
from flask_script import Manager
from flask_migrate import Migrate, MigrateCommand
from db import db
from app import app
from app.models import User,Feed,SharedItem

migrate = Migrate(app, db)

manager = Manager(app)
manager.add_command('db',MigrateCommand)

if __name__ == '__main__':
    manager.run()