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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 make_vertical_box(cls, children, layout=Layout(), duplicates=False):
        "Make a vertical box with `children` and `layout`."
        if not duplicates: return widgets.VBox(children, layout=layout)
        else: return widgets.VBox([children[0], children[2]], layout=layout)