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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 decision_list(n_leaves):
 """ Create a decision list """

    def _list(leaves):
        if len(leaves) == 2:
            return (leaves[0], leaves[1])
        else:
            return (leaves[0], _list(leaves[1:]))
    return _list(np.arange(n_leaves))