title: Functions and if - else in python. Mutliple conditions. Codeacademy
body: <p>Write a function, <code>shut_down</code>, that takes one parameter (you can use anything you like; in this case, we'd use <code>s</code> for string).</p>
  
  <p>The shut_down function should return <code>"Shutting down..."</code> when it gets <code>"Yes"</code>, <code>"yes"</code>, or <code>"YES"</code> as an argument, and <code>"Shutdown aborted!"</code> when it gets <code>"No"</code>, <code>"no"</code>, or <code>"NO"</code>.
  If it gets anything other than those inputs, the function should return <code>"Sorry, I didn't understand you."</code></p>
  
  <p>The code I wrote so far is below. It makes errors, e.g. given <code>"No"</code> as the argument, it does not return <code>"Shutdown aborted!"</code> as expected.</p>
  
  <pre><code>def shut_down(s):
      if s == "Yes" or "yes" or "YES":
          return "Shutting down..."
      elif s == "No" or "no" or "NO":
          return "Shutdown aborted!"
      else:
          return "Sorry, I didn't understand you."
  </code></pre>