foo@bar:~$ pip install -r requirements.txt
foo@bar:~$ export FLASK_APP=app
foo@bar:~$ export FLASK_ENV=development
foo@bar:~$ flask init-db
foo@bar:~$ flask run
foo@bar:~$ pip install -r requirements.txt
foo@bar:~$ export FLASK_APP=app
foo@bar:~$ export FLASK_ENV=development
foo@bar:~$ flask init-db
foo@bar:~$ flask run