title: how reference works in python integer vs list ? in list both value are same, why is in integer section a value is not 2?
body: <p>List reference append code</p>
  
  <pre><code>a = [1,2,3,4,5]
  b = a
  b.append(6)
  print(a)
  print(b)
  #ans:
  [1,2,3,4,5,6]
  [1,2,3,4,5,6]
  </code></pre>
  
  <p>Integer reference in int</p>
  
  <pre><code>a = 1
  b = a
  b +=1
  print(a)
  print(b)
  #ans:
  1
  2
  </code></pre>
  
  <p>how reference works in python integer vs list ? in list both value are same, why is in integer section a value is not 2 ? </p>