code: def hms(self, msg, tic=None, prt=sys.stdout):
          
          if tic is None:
              tic = self.tic
          now = timeit.default_timer()
          hms = str(datetime.timedelta(seconds=(now-tic)))
          prt.write('{HMS}: {MSG}\n'.format(HMS=hms, MSG=msg))
          return now
docs: Print elapsed time and message.