citavi_mapper/frontend/formsets.py

from frontend.models import Presentation, PresentationEvent, PresentationPerson
from django.forms.models import inlineformset_factory

PresentationPersonInlineFormset = inlineformset_factory(
    Presentation,
    PresentationPerson,
    extra=1,
    can_delete=False
)

PresentationEventInlineFormset = inlineformset_factory(
    Presentation,
    PresentationEvent,
    extra=1,
    can_delete=False
)