title: Unable to return in if block while calculating GCD
body: <p>I am trying to calculate a GCD of 2 numbers, the following code block works fine, I am using recursion, but when I am trying to return a value I am not able to do so, <code>return a</code> results in <code>None</code></p>
  
  <pre><code>def gcd(a,b):
      if b == 0:
          print a
          return a   # This is not working 
      else:
          gcd(b,a%b)
  
  XX = gcd(3, 5)
  print (XX)
  </code></pre>
  
  <p>Output:</p>
  
  <pre><code>1
  None
  </code></pre>