title: Difficulty installing Django Debug Toolbar
body: <p>I tried to install Django Panels and ran into an error. I installed using pip -- <code>pip install django-debug-toolbar</code> -- and it seemed to go alright. But when I added it to my project like this: </p>
  
  <pre><code>INSTALLED_APPS = (
      'django.contrib.auth',
      'django.contrib.contenttypes',
      'django.contrib.sessions',
      'django.contrib.staticfiles',
      'django.contrib.sites',
      'django.contrib.admin',
      'django.contrib.flatpages',
      'coltrane',
      'markdown',
      'debug_toolbar',
  )
  </code></pre>
  
  <p>and then ran <code>python manage.py syncdb</code>  got the following error:</p>
  
  <pre><code>python manage.py syncdb
  Traceback (most recent call last):
    File "manage.py", line 10, in &lt;module&gt;
      execute_from_command_line(sys.argv)
    File "/usr/local/Cellar/python/2.7.6/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/Django-1.7.dev20140121103749-py2.7.egg/django/core/management/__init__.py", line 427, in execute_from_command_line
      utility.execute()
    File "/usr/local/Cellar/python/2.7.6/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/Django-1.7.dev20140121103749-py2.7.egg/django/core/management/__init__.py", line 391, in execute
      django.setup()
    File "/usr/local/Cellar/python/2.7.6/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/Django-1.7.dev20140121103749-py2.7.egg/django/__init__.py", line 21, in setup
      apps.populate(settings.INSTALLED_APPS)
    File "/usr/local/Cellar/python/2.7.6/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/Django-1.7.dev20140121103749-py2.7.egg/django/apps/registry.py", line 105, in populate
      app_config.import_models(all_models)
    File "/usr/local/Cellar/python/2.7.6/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/Django-1.7.dev20140121103749-py2.7.egg/django/apps/base.py", line 160, in import_models
      self.models_module = import_module(models_module_name)
    File "/usr/local/Cellar/python/2.7.6/Frameworks/Python.framework/Versions/2.7/lib/python2.7/importlib/__init__.py", line 37, in import_module
      __import__(name)
    File "/usr/local/Cellar/python/2.7.6/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/debug_toolbar/models.py", line 10, in &lt;module&gt;
      from debug_toolbar.middleware import DebugToolbarMiddleware
    File "/usr/local/Cellar/python/2.7.6/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/debug_toolbar/middleware.py", line 13, in &lt;module&gt;
      from debug_toolbar.toolbar import DebugToolbar
    File "/usr/local/Cellar/python/2.7.6/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/debug_toolbar/toolbar.py", line 153, in &lt;module&gt;
      urlpatterns = DebugToolbar.get_urls()
    File "/usr/local/Cellar/python/2.7.6/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/debug_toolbar/toolbar.py", line 147, in get_urls
      for panel_class in cls.get_panel_classes():
    File "/usr/local/Cellar/python/2.7.6/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/debug_toolbar/toolbar.py", line 125, in get_panel_classes
      (panel_module, e))
  django.core.exceptions.ImproperlyConfigured: Error importing debug panel debug_toolbar.panels.signals: "cannot import name WEAKREF_TYPES"
  </code></pre>
  
  <p>I've searched around for answers to this but with no luck. Does anyone know what might be wrong here? Any help would be greatly appreciated.</p>