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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 set_layout(wlayout, callback):
    '''set window layout'''
    global display_size
    global window_list
    global loaded_layout
    global pending_load
    global vehiclename
    #if not wlayout.name in window_list:
    #    print("layout %s" % wlayout)
    if not wlayout.name in window_list and loaded_layout is not None and wlayout.name in loaded_layout:
        callback(loaded_layout[wlayout.name])
    window_list[wlayout.name] = ManagedWindow(wlayout, callback)
    display_size = wlayout.dsize
    if pending_load:
        pending_load = False
        load_layout(vehiclename)