title: Insert element in list python
body: <p>Why this code:</p>
  
  <pre><code>result_list = [[]]*14
  result_list[3].append('sdfda')
  print(result_list)
  </code></pre>
  
  <p>is output:</p>
  
  <pre><code>[['sdfda'], ['sdfda'], ['sdfda'], ['sdfda'], ['sdfda'], ['sdfda'], ['sdfda'], ['sdfda'], ['sdfda'], ['sdfda'], ['sdfda'], ['sdfda'], ['sdfda'], ['sdfda']]
  </code></pre>
  
  <p>but i expect:</p>
  
  <pre><code>[[], [], [], ['sdfda'], [], [], [], [], [], [], [], [], [], []]
  </code></pre>
  
  <p>I want to insert elements by index...but this example of code insert the element in all list of list</p>