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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_active_window():
 """Get the currently focused window """

    active_win = None
    default = wnck.screen_get_default()
    while gtk.events_pending():
        gtk.main_iteration(False)
    window_list = default.get_windows()
    if len(window_list) == 0:
        print "No Windows Found"
    for win in window_list:
        if win.is_active():
            active_win = win.get_name()
    return active_win