pandas, how to access multiIndex dataframe?
<p>Show my code</p>

<pre><code>&gt;&gt;&gt; df = pd.DataFrame({'key1': ['a', 'a', 'b', 'b', 'a'], \
                   'key2': ['one', 'two', 'one', 'two', 'one'], \
                   'data1': np.random.randn(5), \
                   'data2': np.random.randn(5)})

&gt;&gt;&gt; new_df = df.groupby(['key1', 'key2']).mean().unstack()
&gt;&gt;&gt; print new_df
         data1               data2
key2       one       two       one       two
key1
a    -0.070742 -0.598649 -0.349283 -1.272043
b    -0.109347 -0.097627 -0.641455  1.135560 
&gt;&gt;&gt; print new_df.columns
MultiIndex(levels=[[u'data1', u'data2'], [u'one', u'two']],
       labels=[[0, 0, 1, 1], [0, 1, 0, 1]],
       names=[None, u'key2'])
</code></pre>

<p>As you can see, the <strong>MultiIndex</strong> dataframe is different with normal dataframes, so how to access the data in the <strong>MultiIndex</strong> dataframe.</p>