如何使用flutter发送电子邮件？

dependencies:
  mailer: ^3.0.0

import 'package:mailer/mailer.dart';
import 'package:mailer/smtp_server.dart';

void sendEmail() async {
  String username = 'your_email@example.com'; // 发件人邮箱
  String password = 'your_password'; // 发件人邮箱密码

  final smtpServer = gmail(username, password); // 使用Gmail作为SMTP服务器

  final message = Message()
    ..from = Address(username, 'Your Name') // 发件人姓名
    ..recipients.add('recipient@example.com') // 收件人邮箱
    ..subject = 'Test Dart Mailer library :: 😀 :: ${DateTime.now()}' // 邮件主题
    ..text = 'This is the plain text.\nThis is line 2 of the text part.'; // 邮件正文

  try {
    final sendReport = await send(message, smtpServer);
    print('Message sent: ' + sendReport.toString());
  } catch (e) {
    print('Error occurred: $e');
  }
}