if (!(py_res = PyObject_CallMethod(next_di->py_instance, "decode",
"KKO", start_sample, end_sample, data))) {
catch_exception("calling %s decode(): ", next_di->instance_id);
if (!(py_res = PyObject_CallMethod(next_di->py_instance, "decode",
"KKO", start_sample, end_sample, data))) {
catch_exception("calling %s decode(): ", next_di->instance_id);