[Flask] Tutorial, step 3: Installing flaskr as a package. Why?

[John Gabriele]

Hi,

Reading the tutorial docs for Flask, I'm confused about step 3 of the
tutorial: [Installing flaskr as a
package](http://flask.pocoo.org/docs/0.12/tutorial/packaging/). This
step describes using setuptools to install my little webapp package into
my project's venv. Why would I want to do that? I can already run my
webapp without installing it --- it's just `flask run`. Why does this
part of the tutorial want me to install my webapp into my project's
venv?

Thanks,
-- John