text: var util = require('util');
  
  /**
   * Custom error for 404 Not found.
   */
  var NotFoundError = exports.NotFoundError = function () {
      Error.apply(this, arguments);
  };
  
  /**
   * Custom error for 409 Conflict.
   */
  var ConflictError = exports.ConflictError = function() {
      Error.apply(this, arguments);
  };
  
  /**
   * Custom error for 413 Entity Too Large.
   */
  var FileTooBigError = exports.FileTooBigError = function () {
      Error.apply(this, arguments);
  };
  
  /**
   * Custom error for 415 Unsupported Media Type.
   */
  var UnsupportedMediaTypeError = exports.UnsupportedMediaTypeError = function () {
      Error.apply(this, arguments);
  };
  
  // Inherit from Error
  util.inherits(NotFoundError, Error);
  util.inherits(ConflictError, Error);
  util.inherits(FileTooBigError, Error);
  util.inherits(UnsupportedMediaTypeError, Error);