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How to save a django model with manyToMany Through relationship, as well as manyToMany regular relationships

I read everything I can find in ManyToMany relationships in Django, but so far I have not seen anything that solves my specific problem with the ManyToMany-Through relationship along with the simple ManyToMany that Django processes so easily on its own.

Consider these models:

class Treatment(models.Model):
    ...
    book = models.ManyToManyField(Book, through='TreatmentLocation')
    category = models.ManyToManyField(Category)

class Book(models.Model):
    name = models.CharField(...)

class TreatmentLocation(models.Model):
    treatment = models.ForeignKey(Treatment)
    book = models.ForeignKey(Book)
    page = models.CharField(...)

class Category(models.Model):
    name = models.CharField(...)

I have data coming in to a POST array, but stopping browsing seems complicated.

def save_treatment(request):
    form = TreatmentForm(request.POST)

    if form.is_valid():
        treatment = form.save()

        pages = request.POST.getlist('page')
        books = request.POST.getlist('book')

        counter = 0
        for page in pages:
            book_id = books.__getitem__(counter)
            TreatmentLocation.objects.create(treatment_id=treatment.id, book_id=book_id, page=page)
            counter = counter + 1

        form.save_m2m()
    else:
        ...

Processing is successfully saved, as well as in the processing area, but as soon as I try to call save_m2m () to save links like "Treatment category", I get an error Cannot set values on a ManyToManyField which specifies an intermediary model. Use TreatmentLocation Manager.

Does anyone know how to save both of these things? I would like to avoid using raw SQL.

+1
1

through ManyToManyField ModelForm?

class MyForm(forms.ModelForm):
    class Meta:
        exclude = ('book',)
        model = Treatment
+1

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