The QSocketNotifier expects a file descriptor ID as the first parameter of its
constructor. This means, that for now, we have to use something like this:

QSocketNotifier(sys.stdin.fileno(), QSocketNotifier.Read)

To make this more Pythonic, I propose that the QSocketNotifier gets an
additional constructor that accepts a Python file-like object (i.e. any object
that has a .fileno() method that returns the file descriptor ID). Of course,
the old way of specifying the "socket" as integer should still be provided for
flexibility. This way, the socket notifier could be constructed like this:

QSocketNotifier(sys.stdin, QSocketNotifier.Read)

This could roughly look like this (skipping surrounding code for clarity):

def __init__(self, socket, type, parent=0):
    if hasattr(socket, 'fileno'):
       socket = socket.fileno()

    # .. normal code here ..