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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_figure_window_geometry(fig='gcf'):
 """ This will currently only work for Qt4Agg and WXAgg backends. Returns position, size postion = [x, y] size = [width, height] fig can be 'gcf', a number, or a figure object. """


    if type(fig)==str:          fig = _pylab.gcf()
    elif _fun.is_a_number(fig): fig = _pylab.figure(fig)

    # Qt4Agg backend. Probably would work for other Qt stuff
    if _pylab.get_backend().find('Qt') >= 0:
        size = fig.canvas.window().size()
        pos  = fig.canvas.window().pos()
        return [[pos.x(),pos.y()], [size.width(),size.height()]]

    else:
        print("get_figure_window_geometry() only implemented for QtAgg backend.")
        return None