code: function(hexNum, alpha) {
              if(typeof hexNum !== "number") {
                  hexNum = parseInt(hexNum, 16);
              }
              if(isNaN(hexNum) || hexNum < 0x000000 || hexNum > 0xffffff) {
                  return undefined;
              }
              var r = (hexNum & 0xff0000) >> 16,
                  g = (hexNum & 0x00ff00) >> 8,
                  b = hexNum & 0x0000ff;
  
              return ((alpha === undefined) ? ("rgb(" + r + "," + g + "," + b + ")") : ("rgba(" + r + "," + g + "," + b + "," + alpha + ")"));
          }
docs: converts a hex number to its css-friendly counterpart, with optional alpha transparency field returns undefined if the input is cannot be parsed to a valid number or if the number is out of range