code: def _pot_month_counts(self, pot_dataset):
          
          periods = pot_dataset.continuous_periods()
          result = [set() for x in range(12)]
          for period in periods:
              year = period.start_date.year
              month = period.start_date.month
              while True:
                  # Month by month, add the year
                  result[month - 1].add(year)
                  # If at end of period, break loop
                  if year == period.end_date.year and month == period.end_date.month:
                      break
                  # Next month (and year if needed)
                  month += 1
                  if month == 13:
                      month = 1
                      year += 1
          return result
docs: Return a list of 12 sets. Each sets contains the years included in the POT record period.
  
          :param pot_dataset: POT dataset (records and meta data)
          :type pot_dataset: :class:`floodestimation.entities.PotDataset`