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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 prefix(cls, name):
 """ Create a new TreeModel where class attribute names are prefixed with ``name`` """

        attrs = dict([(name + attr, value) for attr, value in cls.get_attrs()])
        return TreeModelMeta(
            '_'.join([name, cls.__name__]),
            (TreeModel,), attrs)