how to set and run flask app on terminal

1> set FLASK_APP=hello
2> flask run
3

1# manage.py
2
3from flask_script import Manager
4
5from myapp import app
6
7manager = Manager(app)
8
9@manager.command
10def hello():
11    print "hello"
12
13if __name__ == "__main__":
14    manager.run()
15