who is the common prime minster of louis mountbattenr and peter carington ?
SELECT DISTINCT var_uri where brack_open dbr_Louis_Mountbatten,_1st_Earl_Mountbatten_of_Burma dbo_primeMinister var_uri sep_dot dbr_Peter_Carington,_6th_Baron_Carrington dbp_primeminister var_uri brack_close