code: func (du *DataURL) String() string {
  	var buf bytes.Buffer
  	du.WriteTo(&buf)
  	return (&buf).String()
  }
docs: // String implements the Stringer interface.
  //
  // Note: it doesn't guarantee the returned string is equal to
  // the initial source string that was used to create this DataURL.
  // The reasons for that are:
  //  * Insertion of default values for MediaType that were maybe not in the initial string,
  //  * Various ways to encode the MediaType parameters (quoted string or url encoded string, the latter is used),