title: The show_letters function should print out each letter of a word on a separate line. Fill in the blanks to make that happen
body: <p>Should print one line per letter</p>
  
  <pre class="lang-py prettyprint-override"><code>def show_letters(word):
      for __:
          print(__)
  
  show_letters("Hello")
  # Should print one line per letter
  </code></pre>