docs: def parse_option(self, option, block_name, *values):
          """ Parse duration option for timer.
              """
  
          try:
              if len(values) != 1:
                  raise TypeError
  
              self.total_duration = int(values[0])
              if self.total_duration <= 0:
                  raise ValueError
  
          except ValueError:
              pattern = u'"{0}" must be an integer > 0'
              raise ValueError(pattern.format(option))