老师您好！如果可能，您能否帮忙看看这样用能否算是使用单例模式？

创造两个文件a.ts 和 b.ts:

a.ts内容如下：

class Talker {
	constructor (private a: string ){
		this.say = this.say.bind(this);
	}
	
	public say(someString: string){
		this.a = someString;
		console.log(`Talker: ${this.a}`);
	}
}

const { say } = new Talker('Should be modified');
export default say;

b.ts内容如下：

import saySomething from './a';

saySomething('Hello World!') // Talker: Hello World!
saySomething('Hello Dell!') // Talker: Hello Dell!