def normalize_ped_delay_row(zone_label, row):
  """
  Normalize the given ped delay row, converting times to ISO 8601 format.
  """
  t = row['t']
  t_iso = t.isoformat()
  data = row['data']
  data['zone'] = zone_label
  return {
    't': t_iso,
    'data': data
  }