code: def _partition_runs_by_day(self):
      
      run_infos = self._get_all_run_infos()
      for x in run_infos:
        ts = float(x['timestamp'])
        x['time_of_day_text'] = datetime.fromtimestamp(ts).strftime('%H:%M:%S')
  
      def date_text(dt):
        delta_days = (date.today() - dt).days
        if delta_days == 0:
          return 'Today'
        elif delta_days == 1:
          return 'Yesterday'
        elif delta_days < 7:
          return dt.strftime('%A')  # Weekday name.
        else:
          d = dt.day % 10
          suffix = 'st' if d == 1 else 'nd' if d == 2 else 'rd' if d == 3 else 'th'
          return dt.strftime('%B %d') + suffix  # E.g., October 30th.
  
      keyfunc = lambda x: datetime.fromtimestamp(float(x['timestamp']))
      sorted_run_infos = sorted(run_infos, key=keyfunc, reverse=True)
      return [{'date_text': date_text(dt), 'run_infos': [x for x in infos]}
              for dt, infos in itertools.groupby(sorted_run_infos, lambda x: keyfunc(x).date())]
docs: Split the runs by day, so we can display them grouped that way.