title: Merging 2 csv files
body: <p>I want to merge 2 csv files. Resulting data frame column should have all the columns from csv 1.
  For ex:</p>
  
  <p><code>df1 = pd.DataFrame({'name': ['foo', 'bar', 'baz', 'foo'],'value': [1, 2, 3, 5]})
  df2 = pd.DataFrame({'class': ['a', 'b', 'c', 'd'],'value': [5, 6, 7, 8]})
  df3 = pd.merge(df1, df2,how='outer')</code></p>
  
  <p>Result df3:
  name value
  foo   1
  bar   2
  baz   3
  foo   5 
  NaN   6 
  NaN   7 
  NaN   8 </p>
  
  <p>How can i get the above result using joins?</p>