'Update an existing hostgroup\'s attributes.'

def update_hostgroup(self, name, new_name=None, description=None):

    cmd = RdxApiCmd(cmd_prefix=[HG_DIR, UPDATE_COMMAND])
    cmd.set_argument(name)
    cmd.add_flag('new-name', new_name)
    cmd.add_flag('description', description)
    return self._run_cmd(cmd)
