template <class T_arg1 = void, class T_arg2 = void, class T_arg3 = void, class T_arg4 = void, class T_arg5 = void, class T_arg6 = void, class T_arg7 = void> </td>
template <class T_arg1 = void, class T_arg2 = void, class T_arg3 = void, class T_arg4 = void, class T_arg5 = void, class T_arg6 = void, class T_arg7 = void> </td>