Result not found

I'm having trouble updating the package from version 1.1.0 to version 1.2.0.
I get this error

The name 'Result' isn't a type, so it can't be used as a type argument.
Try correcting the name to an existing type, or defining a type named 'Result'.dart non_type_as_type_argument

If I go back to version 1.1.0, everything is fine.
flutter_doctor shows that everything is fine.

What would be the way to replace this code with the new version:

```
late final Secretary>? uploadSec;
late final Secretary>? saveSec;

uploadSec = Secretary>(
maxAttempts: 1,
maxConcurrentTasks: 1,
validator: Validators.resultOk,
);

uploadSec!.resultStream.listen((resp) {
if (resp.object != null) {
successTasks.add(resp.object!);
}
});
```