docs: def parse_month_year(date_string):
      """
      >>> parse_month_year('01/10/2012')
      (10, 2012)
      """
      match = re.match('\d{2}/(?P<month>\d{2})/(?P<year>\d{4})$',
                       date_string.lower())
      if not match:
          raise ValueError("Not format 'dd/mm/yyyy': '{}'".format(date_string))
      month = int(match.group('month'))
      year = int(match.group('year'))
      return month, year