text: // Print out code language usage based on level session data
  
  // Usage:
  // mongo <address>:<port>/<database> <script file> -u <username> -p <password>
  
  var total = 0;
  var languages = {};
  var startDate = new ISODate("2014-12-01T00:00:00.000Z")
  var cursor = db['level.sessions'].aggregate(
  [ 
      { $match : {
          //$and: [{codeLanguage: {$exists: true}}, {created : { $gte: startDate}}]
          codeLanguage: {$exists: true}
      }
      },
      { 
          $group : { 
              _id: "$codeLanguage", 
              total: {$sum: 1} 
          }
      },
      {  $sort : { total : -1} }
  ]);
  
  while (cursor.hasNext()) {
    var myDoc = cursor.next();
    total += myDoc.total;
    if (!languages[myDoc._id])
        languages[myDoc._id] = 0
    languages[myDoc._id] += myDoc.total
  }
  print("Total sessions with code languages", total);
  for (key in languages) {
      print(key + "\t" + languages[key] + "\t" + (languages[key] / total * 100).toFixed(2) + "%");
  }