Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

Python Flask with SQLAlchemy Basics Creating a Basic Website with Flask Create a Flask App

Posted by Mat Clark
.a{fill-rule:evenodd;}techdegree
Mat Clark
Python Development Techdegree Student 4,369 Points

Possible bug?

I keep getting a "Bummer: You should have a dunder main statement at the end of your file." message. I passed step 2, which was to add the dunder main statement. But now when I add the route and index function, it tells me this. I don't think I have anything wrong here. Can anybody spot a mistake?

app.py 
from flask import Flask

app = Flask(__name__)

@app.route('/')
def index():
    return 'Hello Flask'

if __name__ == '__main__':
    app.run(port=8000, host='0.0.0.0')

1 Answer

Jennifer Nordell
seal-mask
STAFF
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher
Jennifer Nordell
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher

Hi there, Mat Clark! The only thing I can see that isn't quite right has to do with PEP 8 standards that say that there should be two blank lines after a function definition. So if I add an extra blank line between the return 'Hello Flask' and the "dunder main", the challenge passes.

I'll reach out to the education team to see if this was intended.

Hope this helps! :sparkles:

Chris Freeman
Chris Freeman
Treehouse Moderator 68,457 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,457 Points

The challenge does state to follow PEP008 standards. The regex errors from the challenge checker indicate they are looking for double blank lines following the import, following the app statement, and before the if __name__ statement.