code: function (str) {
           var buffer = JSZip.utils.transformTo("arraybuffer", str);
           return JSZip.utils.arrayBuffer2Blob(buffer);
        }
docs: Create a blob from the given string.
  @param {string} str the string to transform.
  @return {Blob} the result.
  @throws {Error} an Error if the browser doesn't support the requested feature.