docs: def form_valid(self, form):
          # lb = SalesLines.objects.filter(pk=self.__line_pk).first()
  
          # product_old = lb.product_final
          product_pk = self.request.POST.get("product_final", None)
          quantity = self.request.POST.get("quantity", None)
          product_final = ProductFinal.objects.filter(pk=product_pk).first()
          """
          if product:
              is_pack = product.is_pack()
          else:
              is_pack = False
          """
          if product_final and quantity:
              reason = form.data['reason']
              if reason:
                  reason_obj = ReasonModification.objects.filter(pk=reason).first()
                  if reason_obj:
                      try:
                          with transaction.atomic():
                              result = super(LinesUpdateModalBasket, self).form_valid(form)
  
                              reason_basket = ReasonModificationLineBasket()
                              reason_basket.basket = self.object.basket
                              reason_basket.reason = reason_obj
                              reason_basket.line = self.object
                              reason_basket.user = get_current_user()
                              reason_basket.quantity = self.object.quantity
                              reason_basket.save()
                              return result
                      except ValidationError as e:
                          errors = form._errors.setdefault("product_final", ErrorList())
                          errors.append(e)
                          return super(LinesUpdateModalBasket, self).form_invalid(form)
                  else:
                      errors = form._errors.setdefault("reason", ErrorList())
                      errors.append(_("Reason of modification invalid"))
                      return super(LinesUpdatelOrder, self).form_invalid(form)
              else:
                  errors = form._errors.setdefault("reason", ErrorList())
                  errors.append(_("Reason of modification invalid"))
                  return super(LinesUpdatelOrder, self).form_invalid(form)
  
              """
              if is_pack:
                  options = product.productfinals_option.filter(active=True)
                  options_pack = []
                  for option in options:
                      field = 'packs[{}]'.format(option.pk)
                      opt = self.request.POST.get(field, None)
                      if opt:
                          opt_product = ProductFinal.objects.filter(pk=opt).first()
                          if opt_product:
                              options_pack.append({
                                  'product_option': option,
                                  'product_final': opt_product,
                                  'quantity': quantity
                              })
                          else:
                              errors = form._errors.setdefault(field, ErrorList())
                              errors.append(_("Product Option invalid"))
                              return super(LinesUpdateModalBasket, self).form_invalid(form)
                      else:
                          errors = form._errors.setdefault(field, ErrorList())
                          errors.append(_("Option invalid"))
                          return super(LinesUpdateModalBasket, self).form_invalid(form)
              """
          else:
              errors = form._errors.setdefault("product_final", ErrorList())
              errors.append((_("Product invalid"), quantity, product_final))
              return super(LinesUpdateModalBasket, self).form_invalid(form)
  
          """
          ret = super(LinesUpdateModalBasket, self).form_valid(form)
          if product_old != self.object.product:
              self.object.remove_options()
          if is_pack:
              self.object.set_options(options_pack)
          return ret
          """