title: Python Recursion and Tuples
body: <p>I am struggling with this recursion problem. Any help would be greatly appreciated. 
  Write a function named clear that accepts one argument, a tuple of any length, and returns a tuple of the same length with every element set to 0.</p>
  
  <p>Here is my current code:</p>
  
  <pre><code>def clear(tup):
      if len(tup) == 0:
          return tup
      else:
          tup[0] = 0
          return clear(tup - tup[0]) + tup[0]
  </code></pre>