What is `filtering_lookups`?

I’m new to Django. I was reading a model which contains this code:

filtering_lookups = [
    ('title__icontains', 'title',),
    ('description__icontains', 'description'),

I couldn’t find what filtering_lookups does in documentations.
Can anyone explain what the usage of filtering_lookups is?

This is not part of core Django. That means it’s either being used elsewhere in that project or by a third-party library.

It was used somewhere else in views.