def rnp_preprocess(tmpl, dest, defines): """ Generic preprocessing :param BinaryIO tmpl: open filehandle (read) input :param BinaryIO dest: open filehandle (write) output :param dict defines: result of get_defines() :return boolean: """ pp = Preprocessor() pp.setMarker("%") pp.addDefines(defines) pp.do_filter("substitution") pp.out = dest pp.do_include(tmpl, True) return True