File upload error

views.py

    def post(self, request):
        """POST requests"""
        if self.request.POST and self.request.FILES:
            print('picking file ---------')
            csvf = self.request.FILES['file[]']

            print('Found file  --',csvf, 'file---------')
            title = self.request.POST['title']
            user = request.user
            product = Product.objects.create(title=title, file=csvf)

            if not csvf:
                raise ValueError('Kindly select a file for upload')

            try:
                with transaction.atomic():

                    product.save()


                    if user and product:
                        print('processing...... products')
                        async_task('apps.payment.tasks.process_products',
                                   user, product, csvf)


tasks.py

def process_products(user, product, file):
    if user and product:
        reader = csv.reader(file)
            n = next(reader, None)
            print(n)