import tkinter

def get_tk_root():
    try:
        root = tkinter._default_root
    except AttributeError:
        # it is possible to disable default root in Tkinter, although
        # I haven't seen people doing it (but apparently someone did it
        # here).
        root = None

    if root is None:
        # create a new master only if there isn't one already
        root = tkinter.Tk()

    return root


def simulate_mouse_click(widget, x, y):
    """Generate proper events to click at the x, y position (tries to act
    like an X server)."""
    widget.event_generate('<Enter>', x=0, y=0)
    widget.event_generate('<Motion>', x=x, y=y)
    widget.event_generate('<ButtonPress-1>', x=x, y=y)
    widget.event_generate('<ButtonRelease-1>', x=x, y=y)
