Store other key's value in the dart model if first one is null - Flutter

Question

I'm using the json_annotation package to build my dart model.

I have a situation where I need to store either value from the API response in my name key.

API is returning two keys alias and name. In my model, I need to store the value in such a way that, if there is value in alias(not null) the name (in model) will have an alias value. Otherwise, the name(from API) key, will be stored in the model's name key.

Code -

import 'package:json_annotation/json_annotation.dart';

part 'nw_wealth.g.dart';

@JsonSerializable(anyMap: true)
class NwWealth {
 final int accountId;
 final String name;
 final double current;
 final double invested;
 final double gain;
 final String type;
 final double gainPercent;
 final DateTime lastUpdated;

 NwWealth(
   this.name,  // this.name should be = alias ?? name;
   this.current,
   this.invested,
   this.gain,
   this.type,
   this.gainPercent,
   this.accountId,
   this.lastUpdated,
 );

 factory NwWealth.fromJson(Map<String, dynamic> json) =>
     _$NwWealthFromJson(json);

 Map<String, dynamic> toJson() => _$NwWealthToJson(this);
}

Is there a way, where I can store the actual name and alias into the same key in the model based on availability?

I did check the JsonKey() object. But couldn't find a solution.