code: def parse_timespan_value(s):
      
      number, unit = split_number_and_unit(s)
      if not unit or unit == "s":
          return number
      elif unit == "min":
          return number * 60
      elif unit == "h":
          return number * 60 * 60
      elif unit == "d":
          return number * 24 * 60 * 60
      else:
          raise ValueError('unknown unit: {} (allowed are s, min, h, and d)'.format(unit))
docs: Parse a string that contains a time span, optionally with a unit like s.
      @return the number of seconds encoded by the string