title: How to add multiple values to a key in a Python dictionary
body: <p>I am trying to create a dictionary from the values in the <code>name_num</code> dictionary where the length of the list is the new key and the <code>name_num</code> dictionary key and value are the value. So:</p>
  
  <pre><code>name_num = {"Bill": [1,2,3,4], "Bob":[3,4,2], "Mary": [5, 1], "Jim":[6,17,4], "Kim": [21,54,35]}
  </code></pre>
  
  <p>I want to create the following dictionary:</p>
  
  <pre><code>new_dict = {4:{"Bill": [1,2,3,4]}, 3:{"Bob":[3,4,2], "Jim":[6,17,4], "Kim": [21,54,35]}, 2:{"Mary": [5, 1]}}
  </code></pre>
  
  <p>I've tried many variations, but this code gets me the closest:</p>
  
  <pre><code>for mykey in name_num:
      new_dict[len(name_num[mykey])] = {mykey: name_num[mykey]}
  </code></pre>
  
  <p>Output:</p>
  
  <pre><code>new_dict = {4:{"Bill": [1,2,3,4]}, 3:{"Jim":[6,17,4]}, 2:{"Mary": [5, 1]}}
  </code></pre>
  
  <p>I know I need to loop through the code somehow so I can add the other values to key 3.</p>