Registers a function to the display hook queue to be called on hook.
    Look at the sys.displayhook documentation for more information.
    
    :param      func | <callable>

def registerDisplay(func):
    """
    Registers a function to the display hook queue to be called on hook.
    Look at the sys.displayhook documentation for more information.
    
    :param      func | <callable>
    """
    setup()
    ref = weakref.ref(func)
    if ref not in _displayhooks:
        _displayhooks.append(ref)