title: Haskell show data
body: <pre><code>data Months = January|February|March|April|May|June|July
           deriving (Eq, Ord, Enum)
  instance Show Months where 
  
  show January="Jan"
  show February="Feb"
  show March="Mar"
  ....
  </code></pre>
  
  <p>What do I need to do to show the output as such: ”Jan”, ”Feb”, ..., ”July" ?</p>