title: Is there a way to merge multiple list index by index?
body: <p>For example, I have three lists (of the same length)</p>
  
  <pre><code>A = [1,2,3]
  B = [a,b,c]
  C = [x,y,z]
  </code></pre>
  
  <p>and i want to merge it into something like:
  [[1,a,x],[2,b,y],[3,c,z]].</p>
  
  <p>Here is what I have so far:</p>
  
  <pre><code>define merger(A,B,C):
    answer = 
    for y in range (len(A)):
      a = A[y]
      b = B[y]
      c = C[y]
      temp = [a,b,c]
      answer = answer.extend(temp)
    return answer
  </code></pre>
  
  <p>Received error:</p>
  
  <p>'NoneType' object has no attribute 'extend'</p>