title: AttributeError: 'NoneType' object has no attribute 'replace'
body: <p>right sorry that I'm not all good at python 
  but my problem is that i need to replace a character<br>
  here is the thing i am trying to change all i need to change is # to an A for all of the lines</p>
  
  <pre><code>def puzzle():
  print ("#+/084&amp;;")
  print ("#3*#%#+")
  print ("8%203:")
  print (",1$&amp;")
  print ("!-*%")
  print (".#7&amp;33&amp;")
  print ("#*#71%")
  print ("&amp;-&amp;641'2")
  print ("#))85")
  print ("9&amp;330*;")
  </code></pre>
  
  <p>so here is what i attempted to do(it was in another py file)</p>
  
  <pre><code>from original_puzzle import puzzle
  
  puzzle()
  
  result = puzzle()
  
  question = input("first letter ")
  
  for letter in question:
      if letter == "a":
          result = result.replace("#","A")
          print (result)
  </code></pre>
  
  <p>here is what it gives me</p>
  
  <pre><code> Traceback (most recent call last):
    File "N:\AQA 4512;1-practical programming\code\game.py", line 36, in &lt;module&gt;
      result = result.replace("#","A")
  AttributeError: 'NoneType' object has no attribute 'replace'
  </code></pre>
  
  <p>it would help if somebody told me a different way around it aswell
  thanks for the help and sorry again that i'm bad at python </p>