code: def __discoverPlugins():
      
      for app in settings.INSTALLED_APPS:
          if not app.startswith('django'):
              module = __import__(app)
              moduledir = path.Path(module.__file__).parent
              plugin = moduledir / 'frog_plugin.py'
              if plugin.exists():
                  file_, fpath, desc = imp.find_module('frog_plugin', [moduledir])
                  if file_:
                      imp.load_module('frog_plugin', file_, fpath, desc)
  
      return FrogPluginRegistry.plugins
docs: Discover the plugin classes contained in Python files, given a
          list of directory names to scan. Return a list of plugin classes.