title: Python List copy not working in python 3.6
body: <p>When i make a new list via copy from an existing list. The changes i made to new list also reflected in the old list. How can i solve this.</p>
  
  <p>I have used .copy but it failed.</p>
  
  <pre><code># original list
  prediction = [{'seriesname': 'Male', 'data': [681, 696, 711, 726, 739]},
    {'seriesname': 'Female', 'data': [101, 104, 107, 109, 112]}]
  
  # make a copy
  prediction_percentages = prediction.copy()
  # test to check the 2 objects are different
  prediction_percentages is prediction
  False
  
  # Make a change in new list
  prediction_percentages[0]["data"][0] = 1111
  
  # now the changes appear in old list also 
  prediction_percentages
  [{'seriesname': 'Male', 'data': [1111, 696, 711, 726, 739]},
   {'seriesname': 'Female', 'data': [101, 104, 107, 109, 112]}]
  prediction
  [{'seriesname': 'Male', 'data': [1111, 696, 711, 726, 739]},
    {'seriesname': 'Female', 'data': [101, 104, 107, 109, 112]}]
  </code></pre>
  
  <h1>The final result should be</h1>
  
  <pre><code>prediction_percentages
  [{'seriesname': 'Male', 'data': [1111, 696, 711, 726, 739]},
   {'seriesname': 'Female', 'data': [101, 104, 107, 109, 112]}]
  prediction
  [{'seriesname': 'Male', 'data': [681, 696, 711, 726, 739]},
    {'seriesname': 'Female', 'data': [101, 104, 107, 109, 112]}]
  </code></pre>