ChannelUpdate ret_hu_conv = new ChannelUpdate(null, ret);
ret_hu_conv.ptrs_to.add(ret_hu_conv);
ret_hu_conv.ptrs_to.add(contents_arg);
ChannelUpdate ret_hu_conv = new ChannelUpdate(null, ret);
ret_hu_conv.ptrs_to.add(ret_hu_conv);
ret_hu_conv.ptrs_to.add(contents_arg);