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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_list(shapes, types):
 """Get DataDesc list from attribute lists. Parameters shapes : a tuple of (name_, shape_) types : a tuple of (name_, np.dtype) """

        if types is not None:
            type_dict = dict(types)
            return [DataDesc(x[0], x[1], type_dict[x[0]]) for x in shapes]
        else:
            return [DataDesc(x[0], x[1]) for x in shapes]