Remove url field from Course model? and use get_absolute_url method

apps/course/migrations/0027_remove_course_url.py

@@ -0,0 +1,17 @@
+# Generated by Django 2.0.2 on 2018-02-09 08:16
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('course', '0026_auto_20180208_1053'),
+    ]
+
+    operations = [
+        migrations.RemoveField(
+            model_name='course',
+            name='url',
+        ),
+    ]

apps/course/models.py

@@ -2,7 +2,7 @@ import arrow
 from django.db import models
 from django.utils import timezone
 from django.contrib.auth import get_user_model
-
+from django.urls import reverse_lazy
 from polymorphic_tree.models import PolymorphicMPTTModel, PolymorphicTreeForeignKey
 
 from .manager import CategoryQuerySet
@@ -49,7 +49,6 @@ class Course(models.Model):
     category = models.ForeignKey('Category', on_delete=models.PROTECT)
     duration = models.IntegerField('Продолжительность курса', default=0)
     is_featured = models.BooleanField(default=False)
-    url = models.URLField('Ссылка', default='')
     status = models.PositiveSmallIntegerField('Статус', default=0, choices=STATUS_CHOICES)
     likes = models.ManyToManyField(Like, blank=True)
     materials = models.ManyToManyField('Material', blank=True)
@@ -61,6 +60,13 @@ class Course(models.Model):
     created_at = models.DateTimeField(auto_now_add=True)
     update_at = models.DateTimeField(auto_now=True)
 
+    @property
+    def url(self):
+        return self.get_absolute_url()
+
+    def get_absolute_url(self):
+        return reverse_lazy('course', args=[self.id])
+
     @property
     def is_free(self):
         if self.price: