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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 cls_names(cls, wanted_cls, registered=True):
 """ Return a list of attributes for all `wanted_cls` attributes in this class, where `wanted_cls` is the desired attribute type. """

    return [
        fset.name
        for fset in cls_sets(cls, wanted_cls, registered=registered)
    ]