code: private String printTeaStackTraceLines(TeaStackTraceLine[] lines) {
  
          String result = "";
          for (int line = 0; line < lines.length; line++) {
              if (line > 0) {
                  result += '\n';
              }
              result += lines[line].toString();
          }
  
          return result;
      }
docs: Prints the stack trace lines to a String.
  
  @param lines
  @return  the output of the stack trace lines as a string