title: Pandas Plotting with Multi-Index
body: <p>After performing a <code>groupby.sum()</code> on a <code>DataFrame</code> I'm having some trouble trying to create my intended plot.</p>
  <p><img src="https://i.stack.imgur.com/y9L5u.png" alt="grouped dataframe with multi-index" /></p>
  <pre class="lang-py prettyprint-override"><code>import pandas as pd
  import numpy as np
  
  np.random.seed(365)
  rows = 100
  data = {'Month': np.random.choice(['2014-01', '2014-02', '2014-03', '2014-04'], size=rows),
          'Code': np.random.choice(['A', 'B', 'C'], size=rows),
          'ColA': np.random.randint(5, 125, size=rows),
          'ColB': np.random.randint(0, 51, size=rows),}
  df = pd.DataFrame(data)
  
       Month Code  ColA  ColB
  0  2014-03    C    59    47
  1  2014-01    A    24     9
  2  2014-02    C    77    50
  
  dfg = df.groupby(['Code', 'Month']).sum()
  
                ColA  ColB
  Code Month              
  A    2014-01   124   102
       2014-02   398   282
       2014-03   474   198
       2014-04   830   237
  B    2014-01   477   300
       2014-02   591   167
       2014-03   522   192
       2014-04   367   169
  C    2014-01   412   180
       2014-02   275   205
       2014-03   795   291
       2014-04   901   309
  </code></pre>
  <p>How can I create a subplot (<code>kind='bar'</code>) for each <code>Code</code>, where the x-axis is the <code>Month</code> and the bars are <code>ColA</code> and <code>ColB</code>?</p>