The login page does not appear in "example_auth.py"

[hryk0812]

I am using example_auth.py and expect the login page to appear but it does not.
When I run example_auth.py on my PC and access "127.0.0.1:5000" in my PC browser, I see the following page.

I am thinking that the login page is displayed, but is it not?Any advice would be appreciated.

(As additional information, the page is displayed correctly when example_form.py is used. Also, I am using version 1.5.1 of adminui.)