This has been reverted because it caused a bug with input() in Python 3.
I asked hndrewaall on Bitbucket (who originally raise this issue) why they needed it - said
It solved an issue I had while using fabric under bpython. I doubt an irrelevant one would work, but I also had so many other issues with fabric + bpython that I'm not sure special consideration for that use case is justified. Indeed, it is quite possible that I should be coming up with patches on the fabric side :)
'bpython.cli.FakeStdin' should have fileno() method