forms.py

# items/forms.py
from django import forms
from .models import ItemLocation


# define your models forms here
class ItemLocationAdminForm(forms.ModelForm):
    qty_on_hand = forms.IntegerField()
    qty_on_order = forms.IntegerField()
    qty_in_transit = forms.IntegerField()

    class Meta:
        model = ItemLocation
        fields = ['qty_on_hand', 'qty_on_order', 'qty_in_transit']

    def save(self, commit=True):
        qty_on_hand = self.cleaned_data['qty_on_hand']
        qty_on_order = self.cleaned_data['qty_on_order']
        qty_in_transit = self.cleaned_data['qty_in_transit']

        instance = super(ItemLocationAdminForm, self).save(commit=False)
        instance.qty_on_hand = qty_on_hand
        instance.qty_on_order = qty_on_order
        instance.qty_in_transit = qty_in_transit
        if commit:
            instance.save()
        return instance