Move the Property and Triple related filters and methods to the
apis_relations.filters module instead of keeping them in the
apis_entities.filtersets module. This makes the whole module more
readable and moves the filters and methods closer to the models they are
working with. Additionaly, this makes it possible to only import the
fitlers and methods if the apis_relations app is actually part of the
INSTALLED_APPS list.
Move the Property and Triple related filters and methods to the
apis_relations.filtersmodule instead of keeping them in theapis_entities.filtersetsmodule. This makes the whole module more readable and moves the filters and methods closer to the models they are working with. Additionaly, this makes it possible to only import the fitlers and methods if theapis_relationsapp is actually part of the INSTALLED_APPS list.