#NEWLINE# @ classmethod #NEWLINE# def unrank_gray( self , rank , superset ) : #NEWLINE# #INDENT# "\n        Gets the Gray code ordered subset of the specified rank.\n\n        Examples\n        ========\n\n        >>> from sympy.combinatorics.subsets import Subset\n        >>> Subset.unrank_gray(4, ['a', 'b', 'c']).subset\n        ['a', 'b']\n        >>> Subset.unrank_gray(0, ['a', 'b', 'c']).subset\n        []\n\n        See Also\n        ========\n        iterate_graycode, rank_gray\n        " #NEWLINE# graycode_bitlist = GrayCode . unrank ( len ( superset ) , rank ) #NEWLINE# return Subset . subset_from_bitlist ( superset , graycode_bitlist )