title: pandas groupby object to dataframe
body: <pre><code>import pandas as pd
  df1 = pd.DataFrame( {"name" : ["name1", "name1", "name2", "name3", "name3" , "name3"], "item" : ["item1", "item2", "item3", "item2", "item3", "item1"] } )
  df2 = df1.groupby('name')['item']
  </code></pre>
  
  <p>In this groupby object I have all the items for each name. I can visualise this through:</p>
  
  <pre><code>print(df2.apply(list))
  </code></pre>
  
  <p>and get:</p>
  
  <pre><code>name
  name1           [item1, item2]
  name2                  [item3]
  name3    [item2, item3, item1]
  </code></pre>
  
  <p>what I, however, would like to achieve is something like this:</p>
  
  <pre><code>name     itemA    itemB    itemC
  name1    item1    item2    NaN
  name2    item3    NaN      NaN
  name3    item2    item3    item1
  </code></pre>
  
  <p>Any help is much appreciated.</p>