[Twisted-Python] Notification when SSHConnectForwardingChannel is ready for traffic?

Hi, I've managed to implement ssh tunneling using this answer on SO - http://stackoverflow.com/a/23549091/5605324, and the tunnel can be used from another app. However I would like to use it from within the twisted application, but I'm not sure what to wire up so that I can get a callback when the SSHConnectForwardingChannel is ready for traffic. It looks like I can attach a callback to channel's _channelOpenDeferred, but that seems a bit hacky. Any suggestions? Thanks Naveen Michaud-Agrawal