def create_default_groups(self):
        for group in self.groups:
            group = group.replace(" ", "_").lower()
            self[group] = NamedRequirements(group)
def remove_backend(self, backend_id):
        """ Removes a backend from the treeview, and selects the first (to show
        something in the configuration panel

        @param backend_id: the id of the backend to remove
        """
        if backend_id in self.backendid_to_iter:
            self.liststore.remove(self.backendid_to_iter[backend_id])
            del self.backendid_to_iter[backend_id]
            self.select_backend()