title: ModuleNotFoundError: No module named 'debug_toolbar'
body: <p>In trying to make the migrations with <code>python manage.py runserver</code>, I got the following traceback :  </p>
  
  <pre><code>Traceback (most recent call last):
    File "manage.py", line 22, in &lt;module&gt;
      execute_from_command_line(sys.argv)
    File "/home/infinity/.virtualenvs/project/lib/python3.6/site-packages/django/core/management/__init__.py", line 364, in execute_from_command_line
      utility.execute()
    File "/home/infinity/.virtualenvs/project/lib/python3.6/site-packages/django/core/management/__init__.py", line 338, in execute
      django.setup()
    File "/home/infinity/.virtualenvs/project/lib/python3.6/site-packages/django/__init__.py", line 27, in setup
      apps.populate(settings.INSTALLED_APPS)
    File "/home/infinity/.virtualenvs/project/lib/python3.6/site-packages/django/apps/registry.py", line 85, in populate
      app_config = AppConfig.create(entry)
    File "/home/infinity/.virtualenvs/project/lib/python3.6/site-packages/django/apps/config.py", line 94, in create
      module = import_module(entry)
    File "/home/infinity/.virtualenvs/project/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 953, in _find_and_load_unlocked
  ModuleNotFoundError: No module named 'debug_toolbar'
  </code></pre>
  
  <p>Here is a part of the setting file </p>
  
  <pre><code>from .common import *  # noqa
  
  DEV = True
  DEBUG = True
  STAGE = 'dev'
  
  EMAIL_BACKEND = 'django.core.mail.backends.console.EmailBackend'
  
  USERENA_USE_HTTPS = False
  
  ALLOWED_HOSTS = ['127.0.0.1', 'localhost']
  
  INSTALLED_APPS = INSTALLED_APPS + [
      'debug_toolbar',
      'django_extensions',
  ]
  
  MIDDLEWARE = MIDDLEWARE + [
      'debug_toolbar.middleware.DebugToolbarMiddleware',
  ]
  
  DEBUG_TOOLBAR_PANELS = [
      'debug_toolbar.panels.versions.VersionsPanel',
      'debug_toolbar.panels.timer.TimerPanel',
      'debug_toolbar.panels.settings.SettingsPanel',
      'debug_toolbar.panels.headers.HeadersPanel',
      'debug_toolbar.panels.request.RequestPanel',
      'debug_toolbar.panels.sql.SQLPanel',
      'debug_toolbar.panels.staticfiles.StaticFilesPanel',
      'debug_toolbar.panels.templates.TemplatesPanel',
      'debug_toolbar.panels.cache.CachePanel',
      'debug_toolbar.panels.signals.SignalsPanel',
      'debug_toolbar.panels.logging.LoggingPanel',
      'debug_toolbar.panels.redirects.RedirectsPanel',
  ]
  
  DEBUG_TOOLBAR_CONFIG = {
      'INTERCEPT_REDIRECTS': False,
  }
  </code></pre>
  
  <p>I can't explain why this app is never loaded. I am struggling with this problem for a good while now. Could anyone have some time to help me with that?</p>