Django Container with Items - (e.g. inlineformset_factory)

container_with_items.py

from django.forms.models import inlineformset_factory
from django.shortcuts import render


def container_with_items(request, container_id):
    ItemFormSet = inlineformset_factory(
        models.Container, models.Item, form=forms.InlineItemForm, fk_name='container', extra=1
    )

    # Use this to layout the Item forms
    helper = forms.ItemFormSetFormHelper()

    # The container should already exist
    container = models.Container.objects.get(id=int(container_id))

    # The default is to have the formset get the queryset of items. You can over-ride this with the
    # queryset keyword. You can often avoid this by using Model Meta options such as "ordering"
    qs = my_get_queryset()

    # Can also initialize the blank forms using the "initial" keyword
    initial = {'color': 'red'}

    if request.method == "POST":
        formset = ItemFormSet(request.POST, request.FILES, instance=container, initial=initial, queryset=qs)
        if formset.is_valid():
            formset.save()
            return HttpResponseRedirect(reverse('my_url'))
    else:
        formset = ItemFormSet(instance=container, initial=initial, queryset=qs)
    return render(request, "my_form.html", {
        'formset': formset, 'helper': helper, 'container': container
    })