title: NoReverseMatch at / Reverse error with urlresolvers, get_absolute_url()
body: <p>Error with url reverse() in function get_absolute_url()</p>
  
  <h1>can't reverse the url in every  models (serial_slug) but url himself is exists!</h1>
  
  <h1>this is main url.py</h1>
  
  <pre><code>from django.conf.urls import include, url
  from django.contrib import admin
  
  urlpatterns = [
      url(r'^admin/', admin.site.urls),
  
      url(r'^series/', include("serials.urls", namespace='series')),
      url(r'^', include("serials.urls", namespace='homeview')),
  
  ]
  </code></pre>
  
  <h1>this is my urls.py  in my app</h1>
  
  <pre><code>from django.conf.urls import include, url
  from .views import homeview, post_of_serial, post_of_season, post_of_serie
  
  urlpatterns = [
     url(r'^$', homeview, name='homeview'),  # /series/
     url(r'^(?P&lt;serial_slug&gt;[\w-]+)/$', post_of_serial, name='post_of_serial'),  # /series/Prison_Break/
     url(r'^(?P&lt;serial_slug&gt;[\w-]+)/(?P&lt;season_slug&gt;[\w-]+)/$', post_of_season, name='post_of_season'),  # /series/Prison_Break/season_5/
     url(r'^(?P&lt;serial_slug&gt;[\w-]+)/(?P&lt;season_slug&gt;[\w-]+)/(?P&lt;series_slug&gt;[\w-]+)/$', post_of_serie, name='post_of_serie'),  # /series/Prison_Break/season_5/2/  
  
  ]
  </code></pre>
  
  <h1>this is models.py</h1>
  
  <pre><code>class Season(models.Model):
      id                                      = models.AutoField(primary_key=True)
      name_of_the_season                      = models.CharField(max_length=40)
      slug                                    = models.SlugField(unique=False, blank=True) 
      name_for_easy_access                    = models.CharField(max_length=40)
      preview_of_season                       = models.ImageField(upload_to="previews/preview_for_season/", default=None,width_field="width_field", height_field="height_field")
      width_field                             = models.IntegerField(default=150)
      height_field                            = models.IntegerField(default=150)
      number_of_released_series               = models.IntegerField(default=0)
      serial_for_this_season                  = models.ForeignKey("Serial", on_delete=models.CASCADE, default=True)
      a_lot_of_series                         = models.ManyToManyField("Series", default=None, blank=True)
      year                                    = models.IntegerField(default=2017)
      timestamp                               = models.DateTimeField(auto_now_add=True, auto_now=False)
      updated                                 = models.DateTimeField(auto_now_add=False, auto_now=True)
      is_active                               = models.BooleanField(default=True)
  
  
      def get_absolute_url(self):
          return reverse('series:post_of_season', kwargs=
                        {'serial_slug': self.serial_for_this_season.slug,
                        'season_slug': self.slug,
                        })
  
      def __str__(self):
          return "%s" % self.name_for_easy_access
  
      class Meta:
          ordering                            = ["-timestamp"]
          verbose_name                        = 'Season'
          verbose_name_plural                 = 'Seasons'
  
  
  class Serial(models.Model):
      id                                      = models.AutoField(primary_key=True)
      rus_name_of_seriall                     = models.CharField(max_length=40)
      eng_name_of_seriall                     = models.CharField(max_length=40)
      slug                                    = models.SlugField(unique=False, blank=True) 
      number_of_serial                        = models.DecimalField(max_digits=10, decimal_places=2, default=True)
      preview_of_serial                       = models.ImageField(upload_to="previews/preview_for_serials/", default=None,width_field="width_field", height_field="height_field")
      width_field                             = models.IntegerField(default=0)
      height_field                            = models.IntegerField(default=0)
      seasonss                                = models.ManyToManyField(Season, default=None, blank=True)
      timestamp                               = models.DateField(auto_now_add=True)
      end_or_in_proccess                      = models.ForeignKey(Status, default=None)
      timestamp                               = models.DateTimeField(auto_now_add=True, auto_now=False)
      updated                                 = models.DateTimeField(auto_now_add=False, auto_now=True)
      is_active                               = models.BooleanField(default=True)
  
      def get_absolute_url(self):
          return reverse('series:post_of_serial', kwargs={'serial_slug': self.slug})
  
  
      def __str__(self):
          return "%s" % self.rus_name_of_seriall
  
      class Meta:
          ordering                            = ["-timestamp"]
          verbose_name                        = 'Serial'
          verbose_name_plural                 = 'Serials'
  
  
  
  class Series(models.Model):
      id                                      = models.AutoField(primary_key=True)
      rus_name                                = models.CharField(max_length=60) 
      eng_name                                = models.CharField(max_length=60) 
      is_active                               = models.BooleanField(default=True)
      serial_of_this_series                   = models.ForeignKey(Serial, on_delete=models.CASCADE, default=True)
      season_of_this_series                   = models.ForeignKey(Season, on_delete=models.CASCADE, default=True)
      number_of_series                        = models.IntegerField(default=0, blank=True, null=True)
      slug                                    = models.SlugField(unique=False, blank=True) 
      description                             = models.TextField(max_length=700, blank=True, default=None) 
      rating                                  = models.FloatField(default=0, blank=True)  
      timestamp_rus                           = models.DateTimeField(auto_now_add=True, auto_now=False)
      updated                                 = models.DateTimeField(auto_now_add=False, auto_now=True)
      timestamp_eng                           = models.CharField(max_length=60) 
      time_of_series                          = models.DecimalField(max_digits=10, decimal_places=2, default=0)
  
      def get_absolute_url(self):
          return reverse('series:post_of_serie', kwargs=
                        {'serial_slug': self.serial_of_this_series.slug,
                         'season_slug': self.season_of_this_series.slug,
                         'series_slug': self.slug})
  
      def __str__(self):
          return "%s | %s" % (self.rus_name, self.number_of_series)
  
      class Meta:
          ordering                            = ["-timestamp_rus"]
          verbose_name                        = 'Series'
          verbose_name_plural                 = 'Series'
  </code></pre>
  
  <blockquote>
    <p>Reverse for 'post_of_serial' with arguments '()' and keyword arguments
    '{'serial_slug': ''}' not found. 1 pattern(s) tried:
    ['series/(?P[\w-]+)/$']</p>
    
    <p>(lookup_view_s, args, kwargs, len(patterns), patterns)
    django.urls.exceptions.NoReverseMatch: Reverse for 'post_of_serial'
    with arguments '()' and keyword arguments '{'serial_slug': ''}' not
    found. 1 pattern(s) tried: ['series/(?P[\w-]+)/$']</p>
  </blockquote>