code: def verify_frames_aligned(frames, calendar):
      
      indexes = [f.index for f in frames]
      check_indexes_all_same(indexes, message="DataFrame indexes don't match:")
  
      columns = [f.columns for f in frames]
      check_indexes_all_same(columns, message="DataFrame columns don't match:")
  
      start, end = indexes[0][[0, -1]]
      cal_sessions = calendar.sessions_in_range(start, end)
  
      check_indexes_all_same(
          [indexes[0], cal_sessions],
          "DataFrame index doesn't match {} calendar:".format(calendar.name),
      )
docs: Verify that DataFrames in ``frames`` have the same indexing scheme and are
      aligned to ``calendar``.
  
      Parameters
      ----------
      frames : list[pd.DataFrame]
      calendar : trading_calendars.TradingCalendar
  
      Raises
      ------
      ValueError
          If frames have different indexes/columns, or if frame indexes do not
          match a contiguous region of ``calendar``.