// wow this one killed me for a bit. now i should mention i have very little to no javascript experience... 
// i got it though! 
// getting the thing to not put a comma after the last element was the hardest part!

function solution(pairs)
{
  var size = 0, checksize = 1, s = "", key;
  for (key in pairs) 
  {
  	if (pairs.hasOwnProperty(key)) 
    {
    	size++;
    }
  }
  for (key in pairs) 
  {
  	if (pairs.hasOwnProperty(key)) 
    {
    	if(checksize < size) 
      {
  			s = s + key + " = " + pairs[key] + ",";
      }
      else
      {
      	s = s + key + " = " + pairs[key];
      }
      checksize++;
    }
  }
  return s;
}