title: Appending a value to python dictionary value using the key if the value is a multiple array
body: <p>I declared a python dictionary with key and value as multiple array. Is it possible to append an array using the key and value index?</p>
  
  <p>This is the way I initialized the python dictionary cvfoldacc</p>
  
  <pre><code>a = []
  b = [] 
  c = [] 
  d = [] 
  e = [] 
  f = []
  classifiers = [a,b,c,d,e,f]
  cvfoldacc = dict.fromkeys(range(2,11), classifiers) 
  </code></pre>
  
  <p>And the result of this initialization is as follows: </p>
  
  <pre><code>cvfoldacc&gt;&gt;
  
  {2: [[], [], [], [], [], []],
   3: [[], [], [], [], [], []],
   4: [[], [], [], [], [], []],
   5: [[], [], [], [], [], []],
   6: [[], [], [], [], [], []],
   7: [[], [], [], [], [], []],
   8: [[], [], [], [], [], []],
   9: [[], [], [], [], [], []],
   10: [[], [], [], [], [], []]}
  </code></pre>
  
  <p>When I tried to append the first list of key(2) with the code 
  cvfoldacc[2][0].append(8), I am getting the result as:</p>
  
  <pre><code>{2: [[8], [], [], [], [], []],
   3: [[8], [], [], [], [], []],
   4: [[8], [], [], [], [], []],
   5: [[8], [], [], [], [], []],
   6: [[8], [], [], [], [], []],
   7: [[8], [], [], [], [], []],
   8: [[8], [], [], [], [], []],
   9: [[8], [], [], [], [], []],
   10: [[8], [], [], [], [], []]}
  </code></pre>
  
  <p>But the expected answer should be this:</p>
  
  <pre><code>{2: [[8], [], [], [], [], []],
   3: [[], [], [], [], [], []],
   4: [[], [], [], [], [], []],
   5: [[], [], [], [], [], []],
   6: [[], [], [], [], [], []],
   7: [[], [], [], [], [], []],
   8: [[], [], [], [], [], []],
   9: [[], [], [], [], [], []],
   10: [[], [], [], [], [], []]}
  </code></pre>