Body

function(date,format,timeZone){
  var tz = None;
  if (timeZone !== undefined){
    tz = Some(timeZone);
  }
  if (_.isNumber(date) && _.isFinite(date)){
    return DateTimeHelper.formatDate(date,format,tz);
  } else if (_.isString(date)){
    var jsDateLong = Date.parse(date);
    return DateTimeHelper.formatDate(jsDateLong,format,tz);
  } else if (!_.isNumber(date) && "getTime" in date && _.isFunction(date.getTime)){
    return DateTimeHelper.formatDate(date.getTime(),format,tz);
  } else {
    return DateTimeHelper.formatDate(date,format,tz);
  }
}