Comment 0 for bug 1994051

I have an app 'myapp' via cliff-framework.
I accidentally specified the incorrect import in my app 'myapp' and discovered that stevedore in extension.py has no one handler(in attach pic1). Therefore, the message is not displayed anywhere (in attach pic2).

I added an extension.py handler (in attach pic3) and the messages are displayed now (in attach pic4)

I'm wondering if this is a bug or by design?