title: Python appending array to an array
body: <p>I am currently working on DES implementation.In one part of the code I have to append array to an array.Below is my code:  </p>
  
  <pre><code>C0=[1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 1, 1]
  
  def Fiestel():
      C=[]
      C.append(C0)
      temp=[0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1]
      C.append(temp)
      print(C)
  Fiestel()
  </code></pre>
  
  <p>How do I append an array to an existing array.I even tried declaring C as 2d array.Thankx in advance for helping.</p>
  
  <p>Each element is an array itself.</p>
  
  <p><a href="https://i.stack.imgur.com/fYBDF.png" rel="noreferrer"><img src="https://i.stack.imgur.com/fYBDF.png" alt="enter image description here"></a></p>