code: def get_nth_weekday_in_month(year, month, weekday, n=1, start=None):
          
          # If start is `None` or Falsy, no need to check and clean
          if start:
              start = cleaned_date(start)
  
          day = date(year, month, 1)
          if start:
              day = start
          counter = 0
          while True:
              if day.month != month:
                  # Don't forget to break if "n" is too big
                  return None
              if day.weekday() == weekday:
                  counter += 1
              if counter == n:
                  break
              day = day + timedelta(days=1)
          return day
docs: Get the nth weekday in a given month. e.g:
  
          >>> # the 1st monday in Jan 2013
          >>> Calendar.get_nth_weekday_in_month(2013, 1, MON)
          datetime.date(2013, 1, 7)
          >>> # The 2nd monday in Jan 2013
          >>> Calendar.get_nth_weekday_in_month(2013, 1, MON, 2)
          datetime.date(2013, 1, 14)