pub fn close_channel<'a, 'b, 'c>(
    outbound_node: &Node<'a, 'b, 'c>,
    inbound_node: &Node<'a, 'b, 'c>,
    channel_id: &ChannelId,
    funding_tx: Transaction,
    close_inbound_first: bool,
) -> (ChannelUpdate, ChannelUpdate, Transaction)