title: Python- adding two functions together
body: <p>Working on a problem set- here is the Q: </p>
  
  <p>Two function definitions are saved in the same file:
  A function count_vowels has one parameter, a word, and returns the number of vowels in that word.
  A function count_consonants has one parameter, a word, and returns the number of consonants in that word.
  To determine the number of letters in a word, write a one-line body for the following function that calls both count_vowels and count_consonants:</p>
  
  <pre><code>def count_letters(word):
  """ (str) -&gt; int
  
  Return the number of letters in word.
  &gt;&gt;&gt; count_letters('hello')
  5
  &gt;&gt;&gt; count_letters('bonjour')
  7
  """
  # Write the one-line function body that belongs here.
  </code></pre>
  
  <p>My answer: </p>
  
  <pre><code>return count_letters(count_vowels() + count_consonants())
  </code></pre>
  
  <p>Wrong. Why?</p>