title: python program shows errors in arranging element of list in sorted order
body: <p>I wrote this program to join all the elements of sub-lists in a single result empty list and then sort the returned result list. But after i run this program i get a unusual output. I get <code>None</code> on console screen.
  What's wrong here in this code?</p>
  
  <pre><code>n=[[44,45,76,8,678,24,24],[45,45737,45,7373]]
  
  def makelist(lis):
       result= []
       for i in lis:
           for j in i:
             result.append(j)
       return result
  
  print makelist(n).sort()
  </code></pre>