I am receiving that error when I try to visit the detail page of my product model. I have the slug field in the url file, but it doesn't seem to matter.

Model

```
class Product(models.Model):
    product_name= models.CharField(max_length=30, blank=False, null=False, verbose_name="the product name")
    product_slug= models.SlugField(max_length=30, blank=False, null=False, verbose_name="the product slug")
    product_excerpt= models.CharField(max_length=100, blank=False, null=False, verbose_name="product excerpt")
    def _set_product_code(self):
        product_code_temp = hashlib.sha224()
        product_hash = self.product_name
        product_hash = product_hash.encode('utf-8')
        product_code_temp.update(product_hash)
        return product_code_temp.hexdigest()[0:5]
product_code = property(_set_product_code)

```

View

```
class ProductPage(DetailView):
    model = Product
    context_object_name = 'product'
    template_name="product.html"

```

Url

```
url(r'^product/(?P<product_slug>\w+)/(?P<product_code>\w+)/$', ProductPage.as_view(), name="product"),

```

Can anyone pinpoint what I'm doing wrong?