title: Summing the elements of a list recursively
body: <pre><code>def sum(L):
      if len(L) == 1:
          return L[0]
      i = sum (len (L) // 2)
      if  len(L) &gt; 1:
          return i + i
  
  L=[2,4]
  
  print (sum(L))
  </code></pre>
  
  <p>when i try to run it there is a TypeError: object of type 'int' has no len().</p>