code: def get_image(self, title, group):
          '''
          Retrieve image @title from group @group.
          '''
          return self.images[group.lower()][title.lower()f get_image(self, title, group):
          '''
          Retrieve image @title from group @group.
          '''
          return self.images[group.lower()][title.lower()]
docs: Retrieve image @title from group @group.