@Override
    public String toString() {
      return "GistRecord[" +
             "projectId='" + projectId + '\'' +
             ", gistStamp=" + gistStamp +
             ", payload=" + payload +
             ", externalFileSuffix='" + externalFileSuffix + '\'' +
             ", payloadSizeIsUnknown=" + payloadWasChanged +
             ']';
    }
@Override
    public String toString()