[Telepathy] How do I use Interfaces from PyGI tp-glib

[Mystilleef]

I may have run into a problem where some of the methods and
signals in certain interfaces are not exposed in PyGI tp-
glib.

For example, some of the methods and all of the signals in
oft.Channel.Interface.Group are not exposed in PyGI tp-glib.

In particular, I'm trying to add a member to a channel to
start an incoming SIP call. I've prepared the channel with
all the required features (including FEATURES GROUP). So
the channel is READY and PREPARED. However, the channel
object doesn't have an add_member method.

How do I get methods and signals for Interfaces in PyGI
tp-glib?

Thanks