title: django 2.1.3 'django.db.backends.postgis' isn't an available database backend
body: <p>I am trying to use geodjango for a project. Before I use geodjango I'm trying to do a learn it from the following tutorial: <a href="https://docs.djangoproject.com/en/2.1/ref/contrib/gis/tutorial/" rel="nofollow noreferrer">https://docs.djangoproject.com/en/2.1/ref/contrib/gis/tutorial/</a></p>
  
  <p>I originally had django 1.11 installed and tried following that tutorial (stupid of me). However, after uninstalling django 1.11 and installing django 2.1.3 I am encountering some errors.</p>
  
  <p>After I make the model according to the tutorial, I use the command </p>
  
  <pre><code>python3 manage.py makemigrations
  </code></pre>
  
  <p>I end up getting the following error:</p>
  
  <pre><code>Traceback (most recent call last):
    File "/home/aihoque2/.local/lib/python3.6/site- packages/django/db/utils.py", line 110, in load_backend
          return import_module('%s.base' % backend_name)
    File "/usr/lib/python3.6/importlib/__init__.py", line 126, in import_module
      return _bootstrap._gcd_import(name[level:], package, level)
    File "&lt;frozen importlib._bootstrap&gt;", line 994, in _gcd_import
    File "&lt;frozen importlib._bootstrap&gt;", line 971, in _find_and_load
    File "&lt;frozen importlib._bootstrap&gt;", line 941, in _find_and_load_unlocked
    File "&lt;frozen importlib._bootstrap&gt;", line 219, in _call_with_frames_removed
    File "&lt;frozen importlib._bootstrap&gt;", line 994, in _gcd_import
    File "&lt;frozen importlib._bootstrap&gt;", line 971, in _find_and_load
    File "&lt;frozen importlib._bootstrap&gt;", line 953, in _find_and_load_unlocked
  ModuleNotFoundError: No module named 'django.db.backends.postgis'
  
  The above exception was the direct cause of the following exception:
  
  Traceback (most recent call last):
    File "manage.py", line 15, in &lt;module&gt;
      execute_from_command_line(sys.argv)
    File "/home/aihoque2/.local/lib/python3.6/site-packages/django/core/management/__init__.py", line 381, in execute_from_command_line
      utility.execute()
    File "/home/aihoque2/.local/lib/python3.6/site-packages/django/core/management/__init__.py", line 357, in execute
      django.setup()
    File "/home/aihoque2/.local/lib/python3.6/site-packages/django/__init__.py", line 24, in setup
      apps.populate(settings.INSTALLED_APPS)
    File "/home/aihoque2/.local/lib/python3.6/site-packages/django/apps/registry.py", line 112, in populate
      app_config.import_models()
    File "/home/aihoque2/.local/lib/python3.6/site-packages/django/apps/config.py", line 198, in import_models
      self.models_module = import_module(models_module_name)
    File "/usr/lib/python3.6/importlib/__init__.py", line 126, in import_module
      return _bootstrap._gcd_import(name[level:], package, level)
    File "&lt;frozen importlib._bootstrap&gt;", line 994, in _gcd_import
    File "&lt;frozen importlib._bootstrap&gt;", line 971, in _find_and_load
    File "&lt;frozen importlib._bootstrap&gt;", line 955, in _find_and_load_unlocked
    File "&lt;frozen importlib._bootstrap&gt;", line 665, in _load_unlocked
    File "&lt;frozen importlib._bootstrap_external&gt;", line 678, in exec_module
    File "&lt;frozen importlib._bootstrap&gt;", line 219, in _call_with_frames_removed
    File "/home/aihoque2/.local/lib/python3.6/site-packages/django/contrib/auth/models.py", line 2, in &lt;module&gt;
      from django.contrib.auth.base_user import AbstractBaseUser, BaseUserManager
    File "/home/aihoque2/.local/lib/python3.6/site-packages/django/contrib/auth/base_user.py", line 47, in &lt;module&gt;
      class AbstractBaseUser(models.Model):
    File "/home/aihoque2/.local/lib/python3.6/site-packages/django/db/models/base.py", line 101, in __new__
      new_class.add_to_class('_meta', Options(meta, app_label))
    File "/home/aihoque2/.local/lib/python3.6/site-packages/django/db/models/base.py", line 305, in add_to_class
      value.contribute_to_class(cls, name)
    File "/home/aihoque2/.local/lib/python3.6/site-packages/django/db/models/options.py", line 203, in contribute_to_class
      self.db_table = truncate_name(self.db_table, connection.ops.max_name_length())
    File "/home/aihoque2/.local/lib/python3.6/site-packages/django/db/__init__.py", line 33, in __getattr__
      return getattr(connections[DEFAULT_DB_ALIAS], item)
    File "/home/aihoque2/.local/lib/python3.6/site-packages/django/db/utils.py", line 202, in __getitem__
      backend = load_backend(db['ENGINE'])
    File "/home/aihoque2/.local/lib/python3.6/site-packages/django/db/utils.py", line 125, in load_backend
      ) from e_user
  django.core.exceptions.ImproperlyConfigured: 'django.db.backends.postgis' isn't an available database backend.
  Try using 'django.db.backends.XXX', where XXX is one of:
      'mysql', 'oracle', 'postgresql', 'sqlite3'
  </code></pre>
  
  <p>here is my configuration in settings.py:</p>
  
  <pre><code>INSTALLED_APPS = [
      'django.contrib.admin',
      'django.contrib.auth',
      'django.contrib.contenttypes',
      'django.contrib.sessions',
      'django.contrib.messages',
      'django.contrib.staticfiles',
      'django.contrib.gis',
      'world',
  ]
  
  DATABASES = {
      'default': {
          'ENGINE': 'django.db.backends.postgis',
          'NAME': 'XXXX', #redacted
          'USER': 'XXXX', #redacted
          'PASSWORD': 'XXXX', #redacted
          'HOST': 'localhost',
          'PORT': '5432',
  
      }
  }
  </code></pre>
  
  <p>I dealt with this problem originally when I had django 1.11 on python2, but if I even use python3 I still get the error. When I run </p>
  
  <pre><code>python3 -m django version
  </code></pre>
  
  <p>I get '2.1.3'. I am not sure why django 2.1.3 will not take postgis as a backend even though the tutorial tells me it does. Is there perhaps something wrong with my django installation such that when I run </p>
  
  <pre><code>django-admin
  </code></pre>
  
  <p>it runs the 1.11 script instead of the 2.1.3? I am quite lost and this is quite frustrating.</p>