Readline -- cannot bind to both Ctrl-tab and tab at the same time?

[Laura Creighton]

I can reproduce this with Python 2.7.9 (default, Mar  1 2015, 12:57:24)
on my debian unstable system.

On pypy both forms just silently fail to install the binding at all.
Since PyPy has its own readline, this is circumstantial evidence that
readline is the problem.  It's not just you.

Laura