who is the common prime minster of violet attleer and william wedgwood benn ?
SELECT DISTINCT var_uri where brack_open dbr_Violet_Attlee,_Countess_Attlee dbo_primeMinister var_uri sep_dot dbr_William_Wedgwood_Benn,_1st_Viscount_Stansgate dbp_primeminister var_uri brack_close