https://docs.djangoproject.com/en/5.1/ref/models/querysets/#isnull
In Django, a FilterSet is a feature provided by the django-filter library, which allows you to filter querysets based on the parameters passed in a request. It’s similar to Django’s ModelForm but for filtering data. FilterSets are useful when you want to provide users with a way to search or filter data by multiple criteria.
There are filtersets that you can use so that using the fetchAll function you can query for all the companies with just one id “number” or an array of ids.
class NumberInFilter(BaseInFilter, NumberFilter): That’s the function you use.
https://www.django-rest-framework.org/api-guide/filtering/
there’s an example of filterset_classin
https://www.django-rest-framework.org/api-guide/filtering/#overriding-the-initial-queryset (edited)