title: Saving DataFrame names as .csv file names in Pandas
body: <pre><code>In [37]: blue = pd.DataFrame({'A': ['foo','foo','foo','bar','bar'], 'B': [4.0, 4.0, 5.0, 8.0, 8.0]})
  
  In [38]: blue
  Out[38]: 
       A  B
  0  foo  4
  1  foo  4
  2  foo  5
  3  bar  8
  4  bar  8
  
  In [39]: red = pd.DataFrame({'A': ['foo','foo','foo','bar','bar'], 'B': [np.nan, np.nan, np.nan, np.nan, np.nan]})
  
  In [40]: red
  Out[40]: 
       A   B
  0  foo NaN
  1  foo NaN
  2  foo NaN
  3  bar NaN
  4  bar NaN
  
  In [41]: for df in [blue, red]:
     ....:     df.to_csv(str(df))
     ....:     
  
  In [42]: !ls
       A  B?0  foo  4?1  foo  4?2  foo  5?3  bar  8?4  bar  8       A   B?0  foo NaN?1  foo NaN?2  foo NaN?3  bar NaN?4  bar NaN  postinstall.sh  vagrant
  </code></pre>
  
  <p>I have some DataFrames. I loop over each DataFrame to work on them. At the end of the loop I want to save each DataFrame as a .csv file named after the DataFrame. I know that it's generally difficult to stringify the name of a variable in Python, but I have to think that I'm missing something obvious here. There is no "name" attribute for DataFrames, so what do I do?</p>