Django Regoup - Sum in templates

[aXXyss Soluciones]

Hi, I want to get the Volume subtotal of my "Contracts" field grouped in my template.

I manage to display the total but not the subtotal.

models.py

class TransColisCgDlaDet(models.Model):

id_trans_colis = models.AutoField(primary_key=True)

essence = models.CharField(max_length=15, blank=True, null=True, verbose_name='Essence')

num_colis = models.CharField(max_length=15, blank=True, null=True, verbose_name='Numéro de Colis')

cubage = models.DecimalField(max_digits=6, decimal_places=3, blank=True, null=True, verbose_name='Cubage')

num_contrat = models.CharField(max_length=15, blank=False, null=True, verbose_name='Numéro de Contrat')

class Meta:

managed = True

db_table = 'TransColisCgDlaDet'

verbose_name = 'Transport de Colis Détaillé '

verbose_name_plural = 'Transports de Colis Détaillés'

ordering = ['num_colis']

def __str__(self):

return str(self.num_colis)

views.py

class TransportDetListView(LoginRequiredMixin,ListView):

login_url = 'admin:login'

model = TransColisCgDlaDet

template_name = "transports/trans_detail.html"

paginate_by = 15

def get_queryset(self):

queryset =  TransColisCgDlaDet.objects.filter(code_trans__contains=self.kwargs['code_trans']).order_by('num_contrat','essence',' 'num_colis')

lstcolis = queryset.values(

'num_contrat'

).annotate(volcolis=Sum('cubage')).annotate(nb_elts=Sum('nbre_elts'))

return lstcolis

I would the subtotal for the contrats y the template:

Contrat: 2475

-----------------------------------------------------

Essence  /  Num Colis  /  Cubage

SIPO  /  22  /  2,378

SIPO  /  23  /  1.251

------------------------------------------------------

Subtotal : 3,629

Contrat: 2500

----------------------------------------------------

Essence  /  Num Colis  /  Cubage

SAPELLI  /  572  /  3.001

SAPELLI  /  573  /  1.501

------------------------------------------------------

Subtotal : 4.502

TOTAL:  8.131

Any ideas for how manage this?

Thanks