title: Pandas flatten Hierarchical Multi-index
body: <p>I have a pandas data frame as follows after attempting to flatten it:</p>
  <pre><code>df = pd.DataFrame(web.DataReader(stocks, 'yahoo', day, day).iloc[0]).unstack(level=0).droplevel(level=0, axis=1)
  
  Attributes     adjClose        close  ...       volume       date
  Symbols                               ...                        
  FB           261.399994   261.399994  ...   13587000.0 2020-10-19
  AAPL         115.980003   115.980003  ...  120639300.0 2020-10-19
  AMZN        3207.209961  3207.209961  ...    5223600.0 2020-10-19
  GOOG        1534.609985  1534.609985  ...    1607100.0 2020-10-19
  NFLX                NaN          NaN  ...          NaN 2020-10-19
  </code></pre>
  <p>I'm trying to persist this to the database; however, I don't see Symbols in the df.columns.
  In order to save the df to a following format:</p>
  <pre><code>Symbols       adjClose        close  ...       volume       date 
  FB           261.399994   261.399994  ...   13587000.0 2020-10-19
  AAPL         115.980003   115.980003  ...  120639300.0 2020-10-19
  AMZN        3207.209961  3207.209961  ...    5223600.0 2020-10-19
  GOOG        1534.609985  1534.609985  ...    1607100.0 2020-10-19
  NFLX                NaN          NaN  ...          NaN 2020-10-19
  </code></pre>
  <p>Any suggestions on how to achieve this? My database has a composite key on Symbols, date columns.
  Thank You.</p>