Unable to save multiple objects from admin panel

Using Django The Admin
1

I have a very simple Model:

class SomeParentModel(models.Model):
    description   = models.TextField(max_length=512, blank=True)
    created         = models.DateTimeField(auto_now_add=True)

class SomeModel(SomeParentModel):
    number = models.BigIntegerField() # not unique!
    created_date = models.DateTimeField(auto_now_add=True)
    somefield = models.ForeignKey(...)
    someotherfield = models.BooleanField(blank=True)

and I want to save multiple instances of Nbr objects at once:

class SomeModelSetForm(forms.ModelForm):
    last_number = Nbr.objects.order_by("-number").first().number
    start_number = forms.IntegerField(required=True, initial=last_number+1)
    end_number = forms.IntegerField(required=True, initial=last_number+1)
    
    class Meta:
        model = SomeModel
        fields = ["start_number", "end_number", ...]
        exclude = ["number"]

    def clean(self):
        cleaned_data = super().clean()
        s = int(cleaned_data["start_number"])
        e = int(cleaned_data["end_number"]) + 1
        self.numbers = [n for n in range(s, e)]

    def save(self, commit=False)
        instances = []
        for nbr in self.numbers:
            instances.append(SomeModel(number=nbr, ....))
        SomeModel.objects.bulk_create(instances)
        return instances    ## tried: return instances[0]

This leads to an AttributeError: 'list' object has no attribute 'save'
So I thought I could maybe just return the last object from instances which throws the error: AttributeError: 'SomeModelSetForm' object has no attribute 'save_m2m'. Did you mean: '_save_m2m'?

How can i create one object per number in my numbers list correctly or how can I call a new save method for every element in my list?

2

I was able to do what I intended by faking a return model instance, but I would love to know if there is a better solution:

def save(self, commit=False)
    instances = []
    for nbr in self.numbers:
        instances.append(SomeModel(number=nbr, ....))
    SomeModel.objects.bulk_create(instances)
    fake = super(SomeModelSetForm, self).save(commit=False)
    fake.uid = 0
    return fake
3

i already found the caveat:

I issue different forms on weather it is a new form or change form, and I had to add:

def get_form(self, request, obj=None, change=False, **kwargs):
    if change == True or obj:
        return SomeModelSingleForm
    return SomeModelSetForm

because get_form is being called twice (maybe a super() somewhere?)