Is there any way to use ajax-select AutoCompleteSelectMultipleField model like ModelMultipleChoiceField

I wanna use ajax-select AutoCompleteSelectMultipleField but I have a problem using typical django methods on it.
I was using a custom model based on the django default ModelMultipleChoiceField for many to many select and I used to call queryset on the returned result from it:

# form
people = CustomizedModelMultipleChoiceField(
        Person.objects.exclude(is_healthy=True).filter(death_date=None))

# test
people_list = form.fields['people'].queryset.values_list('id')

but now I want to use AutoCompleteSelectMultipleField for lazy loading and it raises this error:

AttributeError: 'AutoCompleteSelectMultipleField' object has no attribute 'queryset'