title: Bot replying to a message from a specific user - Discord.py
body: <p>Only the specific user and the specific word can the bot input</p>
  <pre><code>example:
  THE SPECIFIC USER : User1
  THE SPECIFIC WORD : PASSCODE
  -----------------------
  User1: Hello (didn't input)
  User2: PASSCODE (didn't input)
  User1: PASSCODE (input)
  BOT  : RESPOND
  </code></pre>