url() got an unexpected keyword argument 'namespace'
<p>New to Django here, so pardon the rookie question...</p>

<p>I'm getting the <code>url() got an unexpected keyword argument 'namespace'</code> error when I try to call on the <code>reverse</code> function. Tried a few different ways to fix it but nothing seems to be working. Any advice would be greatly appreciated. Please see my code below:</p>

<pre><code>TypeError at /comments/topic-create/
url() got an unexpected keyword argument 'namespace'
Request Method: POST
Request URL:    http://127.0.0.1:8000/comments/topic-create/
Django Version: 1.8.6
Exception Type: TypeError
Exception Value:    
url() got an unexpected keyword argument 'namespace'
</code></pre>

<p><strong>models.py</strong></p>

<pre><code>from django.db import models
from django.conf import settings
from django.utils.text import slugify
from django.core.urlresolvers import reverse

class Topic(models.Model):
    title = models.CharField(max_length=50)
    stock = models.ManyToManyField(Stock)
    slug = models.SlugField(max_length=200, blank=True)
    created = models.DateField(auto_now_add=True,
                               db_index=True)

    def __str__(self):
        return self.title

    def save(self, *args, **kwargs):
        if not self.slug:
            self.slug = slugify(self.title)
            super(Topic, self).save(*args, **kwargs)

    def get_absolute_url(self):
        return reverse('comments:topic_detail', args=[self.id, self.slug])
</code></pre>

<p><strong>forms.py</strong></p>

<pre><code>from django import forms
from .models import Topic

class TopicCreateForm(forms.ModelForm):
    class Meta:
        model = Topic
        fields = ('__all__')
</code></pre>

<p><strong>views.py</strong></p>

<pre><code>from django.shortcuts import render, redirect, get_object_or_404
from django.contrib.auth.decorators import login_required
from .forms import TopicCreateForm
from django.contrib import messages
from .models import Stock, Topic, Comment
# from django.core.urlresolvers import reverse_lazy

@login_required
def topic_create(request):
    if request.method == 'POST':
        form = TopicCreateForm(data=request.POST)
        if form.is_valid():
            cd = form.cleaned_data
            new_item = form.save(commit=False)
            new_item.user = request.user
            new_item.save()
            messages.success(request, 'Topic added successfully')
            # redirect to new created topic detail view
            return redirect(new_item.get_absolute_url())
    else:
        form = TopicCreateForm(data=request.GET)

    return render(request,
                  'comments/comment/topic-create.html',
                  {'section': 'topic',
                   'form': form})

def topic_detail(request, namespace, id, slug):
    topic = get_object_or_404(Topic, id=id, slug=slug)
    return render(request,
                  'comments/comment/topic-detail.html',
                  {'section': 'topic',
                   'topic': topic})
</code></pre>

<p><strong>comments/urls.py</strong></p>

<pre><code>from django.conf.urls import url
from . import views

urlpatterns = [
    url(r'^topic-create/$', views.topic_create, name='create-topic'),
    url(r'topic-detail/(?P&lt;id&gt;\d+)/(?P&lt;slug&gt;[-\w]+)/$',
        views.topic_detail, name='topic-detail'),
]
</code></pre>

<p><strong>mysite/urls.py</strong></p>

<pre><code>from django.conf.urls import include, url
from django.contrib import admin

urlpatterns = [
    url(r'^admin/', include(admin.site.urls)),
    url(r'^account/', include('account.urls')),
    url(r'^comments/', include('comments.urls'),
                namespace='comments'),
]
</code></pre>