title: How to get specific member username with discord.js
body: <p>I would like to add one specific member information (username + avatar) into an embed message. Does someone know how to do that?</p>
  
  <pre><code>const feedback = new discord.RichEmbed()
  .setColor([0, 0, 255])
  .setFooter("Bot created by : " + message.author.username, message.author.avatarURL)
  .setDescription("The text I want to be sent")
  </code></pre>
  
  <p>On the code above, I would like to change "message.author.username" and "message.author.avatarUrl" by a specific discord member identification id such as : 436577130583949315 for example.</p>
  
  <p>However I don't know what is the way from that discord identification number to be able to show the username and the avatar.</p>
  
  <p>Thanks in advance for your help :)</p>