application.py

from flask import Flask
from flask_sqlalchemy import SQLAlchemy
from flask_migrate import Migrate
from flaskext.markdown import Markdown

# setup db
db = SQLAlchemy()

def create_app(**config_overrides):
    app = Flask(__name__)

    # Load config
    app.config.from_pyfile('settings.py')

    # apply overrides for tests
    app.config.update(config_overrides)

    # initialize db
    db.init_app(app)
    migrate = Migrate(app, db)

    # Markdown
    Markdown(app)

    # import blueprints
    from author.views import author_app
    from blog.views import blog_app

    # register blueprints
    app.register_blueprint(author_app)
    app.register_blueprint(blog_app)

    return app