title: Box Plot of a many Pandas Dataframes
body: <p>I have three dataframes containing 17 sets of data with groups A, B, and C. A shown in the following code snippet</p>
  
  <pre><code>import pandas as pd
  import numpy as np
  data1 = pd.DataFrame(np.random.rand(17,3), columns=['A','B','C'])
  data2 = pd.DataFrame(np.random.rand(17,3)+0.2, columns=['A','B','C'])
  data3 = pd.DataFrame(np.random.rand(17,3)+0.4, columns=['A','B','C'])
  </code></pre>
  
  <p>I would like to plot a box plot to compare the three groups as shown in the figure below
  <a href="https://i.stack.imgur.com/NncDU.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/NncDU.jpg" alt="enter image description here"></a>
  I am trying make the plot using <a href="http://seaborn.pydata.org/generated/seaborn.boxplot.html" rel="noreferrer">seaborn's box plot</a> as follows</p>
  
  <pre><code>import seaborn as sns
  sns.boxplot(data1, groupby='A','B','C') 
  </code></pre>
  
  <p>but obviously this does not work. Can someone please help?</p>