postgresql create data file path from application using userchangelog.xml file a

Question

How to create data file path if not exists in postgres server using userchangelog.xml file changeset id

i tried following ways but getting many errors. can any one suggest how can we create data file path from the application if it doesn't exist at the location while creating database using changesets

   DO $$ DECLARE
   BEGIN
   PERFORM pg_catalog.pg_stat_file('${DATAFILEPATHNAME}', false);
   EXCEPTION WHEN undefined_file THEN        
        EXECUTE format('mkdir -p %s', '${DATAFILEPATHNAME}');
     
   END;
   $$ LANGUAGE plpgsql;