title: django CMS blog application TypeError: __init__() missing 1 required positional argument: 'on_delete'
body: <p>Python 3.7.3
  django version 2.2.1</p>
  
  <p>I've just started learning django and have gone through their polls tutorial. </p>
  
  <p>I'm trying to install django CMS package
  <a href="https://github.com/nephila/djangocms-blog" rel="nofollow noreferrer">https://github.com/nephila/djangocms-blog</a></p>
  
  <p>After running python3 manage.py migrate I'm getting following error:</p>
  
  <p><strong>TypeError: __init__() missing 1 required positional argument: 'on_delete'</strong></p>
  
  <p>I've read the solution suggested on <a href="https://stackoverflow.com/questions/44026548/getting-typeerror-init-missing-1-required-positional-argument-on-delete">Getting TypeError: __init__() missing 1 required positional argument: &#39;on_delete&#39; when trying to add parent table after child table with entries</a> but it doesn't resolve</p>
  
  <p>How to fix it?</p>
  
  <p>Following is my models.py</p>
  
  <pre><code>class Choice(models.Model):
  question = models.ForeignKey(Question, on_delete=models.CASCADE)
  choice_text = models.CharField(max_length=200)
  votes = models.IntegerField(default=0)
  def __str__(self):
      return self.choice_text
  </code></pre>
  
  <p>settings.py</p>
  
  <pre><code>INSTALLED_APPS = [
  
  'django.contrib.sites',
  
  'polls.apps.PollsConfig',
  'django.contrib.admin',
  'django.contrib.auth',
  'django.contrib.contenttypes',
  'django.contrib.sessions',
  'django.contrib.messages',
  'django.contrib.staticfiles',
  
  # CMS Blog
  'cms',
  'menus',
  'filer',
  'easy_thumbnails',
  'aldryn_apphooks_config',
  'cmsplugin_filer_image',
  'parler',
  'taggit',
  'taggit_autosuggest',
  'meta',
  'sortedm2m',
  'djangocms_blog',
  ]
  </code></pre>