How to use the puppetboard.app.app function in puppetboard

def test_form_valid(capsys):
    for form in [forms.QueryForm]:
        with app.app.test_request_context():
            qf = form()
            out, err = capsys.readouterr()
            assert qf is not None
            assert err == ""
            assert out == ""

def test_error_forbidden(mock_puppetdb_environments):
    with app.app.test_request_context():
        (output, error_code) = forbidden(None)
        soup = BeautifulSoup(output, 'html.parser')

        long_string = "%s %s" % ('What you were looking for has',
                                 'been disabled by the administrator')
        assert long_string in soup.p.text
        assert error_code == 403

from __future__ import unicode_literals
from __future__ import absolute_import
import os
import subprocess

# Set PUPPETBOARD_SETTINGS to your settings.py
from puppetboard.app import app

if __name__ == '__main__':
    # Start CoffeeScript to automatically compile our coffee source.
    # We must be careful to only start this in the parent process as
    # Werkzeug will create a secondary process when using the reloader.
    if os.environ.get('WERKZEUG_RUN_MAIN') is None:
        try:
            subprocess.Popen([
                app.config['DEV_COFFEE_LOCATION'], '-w', '-c',
                '-o', 'puppetboard/static/js',
                'puppetboard/static/coffeescript'
            ])
        except OSError:
            app.logger.error(
                'The coffee executable was not found, disabling automatic '
                'CoffeeScript compilation'
            )

    # Start the Flask development server
    app.debug = True
    app.run(app.config['DEV_LISTEN_HOST'], app.config['DEV_LISTEN_PORT'])