name the office holder whose predecessor is ernest pollock and successor is john hobson ?
SELECT DISTINCT var_uri where brack_open var_uri dbp_predecessor dbr_Ernest_Pollock,_1st_Viscount_Hanworth sep_dot var_uri dbp_successor dbr_John_Hobson_ attr_open politician attr_close sep_dot var_uri a dbo_OfficeHolder brack_close