如何根据多个对象在Dart中的相同值合并这些对象？

import 'package:collection/collection.dart';

class Person {
  final String name;
  final int age;

  Person(this.name, this.age);
}

void main() {
  List<Person> persons = [
    Person('Alice', 25),
    Person('Bob', 30),
    Person('Charlie', 25),
    Person('Dave', 30),
  ];

  Map<int, List<Person>> mergedPersons = groupListsBy(persons, (person) => person.age);

  mergedPersons.forEach((age, persons) {
    print('Age $age:');
    persons.forEach((person) {
      print('- ${person.name}');
    });
  });
}

Age 25:
- Alice
- Charlie
Age 30:
- Bob
- Dave