I'm developing a Django project and deploying it to OpenShift PaaS. At first everything worked, but after some changes irrelevant to template system (I added django-hosts) something broke there and a "module object 'template' has no attribute 'loader'" error started to appear. What was even stranger, it appeared only two times after each wsgi app restart, and on 3rd request everything started to work. I went back to last commit before breakage, but the problem persisted. I recreated project from scratch and reinstalled my Django app, but it didn't go either; error started appearing every time, not just with first 2 requests.
from django import template really imports template module object, but this object lacks about 5 attributes, including loader, as compared to what expected.
Then I noticed that same thing happens if I try to run the same code from Django shell locally. But it still works in my app's views.py with local Django development server. And in used to work in OpenShift initially. I tried replacing from django import template with from django.template import loader and calling loader directly - and EVERYTHING WORKED
I think I don't understand something about Python import. What's the difference between
import a
a.b
and
from a import b
b
?
Why can a.b in first example miss attributes b has in second one?