title: NoReverseMatch - reverse for ' ' with keyword arguments 'pk' not found
body: <p>im pretty sure this is a simple error but I cant seem to figure it out. The error states that the keyword arguments are not found but i have them in the the html. </p>
  
  <p>here is error: </p>
  
  <pre><code>NoReverseMatch at /questions/questionupdate/user2-question3/4/
  Reverse for 'detail' with keyword arguments '{'pk': 4}' not found. 1 pattern(s) tried: ['questions/questiondetail/(?P&lt;slug&gt;[\\w-]+)/(?P&lt;pk&gt;\\d+)/$']
  Request Method: GET
  Request URL:    http://127.0.0.1:8000/questions/questionupdate/user2-question3/4/
  Django Version: 1.11
  Exception Type: NoReverseMatch
  Exception Value:    
  Reverse for 'detail' with keyword arguments '{'pk': 4}' not found. 1 pattern(s) tried: ['questions/questiondetail/(?P&lt;slug&gt;[\\w-]+)/(?P&lt;pk&gt;\\d+)/$']
  
  file structure:
  project: UserTest
  ---&gt;app:accounts
  ---&gt;app:questions
  </code></pre>
  
  <p><strong>models.py</strong></p>
  
  <pre><code>class Question(models.Model):
      class Meta:
          ordering = ['-date_updated']
      user = models.ForeignKey(User, related_name="question")
      # completedTODO: get user working^
      question = models.TextField(blank=False, null=False) # unique=True,
      question_html = models.TextField(blank=False, null=False)
      answer = models.TextField(blank=False, null=False)
      answer_html = models.TextField(blank=False, null=False)
      slug = models.SlugField(unique=True, default='')
      tags = TaggableManager()
  
      def __str__(self):
          return self.question
  
      def save(self, *args, **kwargs):
          self.question_html = misaka.html(self.question)
          self.answer_html = misaka.html(self.answer)
          super().save(*args, **kwargs)
  
      def get_absolute_url(self):
          return reverse(
              "questions:detail",
              kwargs={
                  # "slug": self.slug,
                  "pk": self.pk
              }
          )
  </code></pre>
  
  <p><strong>urls.py</strong> i am trying to pass both slug and pk to url</p>
  
  <pre><code>url(r'questiondetail/(?P&lt;slug&gt;[\w-]+)/(?P&lt;pk&gt;\d+)/$', views.QuestionDetail.as_view(), name='detail'),
  url(r'questionupdate/(?P&lt;slug&gt;[\w-]+)/(?P&lt;pk&gt;\d+)/$', views.QuestionUpdate.as_view(), name='update'),
  </code></pre>
  
  <p><strong>views.py</strong></p>
  
  <pre><code>class QuestionDetail(generic.DetailView):
      model = models.Question
  
  class QuestionUpdate(generic.UpdateView):
      model = models.Question
      form_class = QuestionForm
      template_name = "questions/question_form_update.html"
  </code></pre>
  
  <p><strong>question_detail.html</strong></p>
  
  <pre><code>&lt;h3&gt;&lt;a href="#"&gt;{{ question.user }}&lt;/a&gt;&lt;/h3&gt;
  &lt;h3&gt;{{ question.question_html|safe }}&lt;/h3&gt;
  &lt;h3&gt;{{ question.answer_html|safe }}&lt;/h3&gt;
  &lt;a href="{% url 'questions:update' slug=question.slug pk=question.pk %}"&gt;Update Question&lt;/a&gt;
  </code></pre>
  
  <p>Any help is appreciated!</p>