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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 search_index_path(self, index=None, **options):
 """ Builds a Yokozuna search index URL. :param index: optional name of a yz index :type index: string :param options: optional list of additional arguments :type index: dict :rtype URL string """

        if not self.yz_wm_index:
            raise RiakError("Yokozuna search is unsupported by this Riak node")
        if index:
            quote_plus(index)
        return mkpath(self.yz_wm_index, "index", index, **options)