name the common home port of the usns yano and noaas mount mitchell ?
SELECT DISTINCT var_uri where brack_open dbr_USNS_Yano_ attr_open T-AKR-297 attr_close dbo_homeport var_uri sep_dot dbr_NOAAS_Mount_Mitchell_ attr_open S_222 attr_close dbo_homeport var_uri brack_close