title: pivot irregular dictionary of lists into pandas dataframe
body: <p>(Or a list of lists...  I just edited)</p>
  
  <p>Is there an existing python/pandas method for converting a structure like this</p>
  
  <pre><code>food2 = {}
  food2["apple"]   = ["fruit", "round"]
  food2["bananna"] = ["fruit", "yellow", "long"]
  food2["carrot"]  = ["veg", "orange", "long"]
  food2["raddish"] = ["veg", "red"]
  </code></pre>
  
  <p>into a pivot table like this?</p>
  
  <pre><code>+---------+-------+-----+-------+------+--------+--------+-----+
  |         | fruit | veg | round | long | yellow | orange | red |
  +---------+-------+-----+-------+------+--------+--------+-----+
  | apple   | 1     |     | 1     |      |        |        |     |
  +---------+-------+-----+-------+------+--------+--------+-----+
  | bananna | 1     |     |       | 1    | 1      |        |     |
  +---------+-------+-----+-------+------+--------+--------+-----+
  | carrot  |       | 1   |       | 1    |        | 1      |     |
  +---------+-------+-----+-------+------+--------+--------+-----+
  | raddish |       | 1   |       |      |        |        | 1   |
  +---------+-------+-----+-------+------+--------+--------+-----+
  </code></pre>
  
  <p>Naively, I would probably just loop through the dictionary.  I see how I can use a map on each inner list, but I don't know how to join/stack them over the dictionary.  Once I did join them, I could just use pandas.pivot_table</p>
  
  <pre><code>for key in food2:
      attrlist = food2[key]
      onefruit_pairs = map(lambda x: [key, x], attrlist)
      one_fruit_frame = pd.DataFrame(onefruit_pairs, columns=['fruit', 'attr'])
      print(one_fruit_frame)
  
       fruit    attr
  0  bananna   fruit
  1  bananna  yellow
  2  bananna    long
      fruit    attr
  0  carrot     veg
  1  carrot  orange
  2  carrot    long
     fruit   attr
  0  apple  fruit
  1  apple  round
       fruit attr
  0  raddish  veg
  1  raddish  red
  </code></pre>