A subclass of the ISO8601::Duration object that use `task calc` to parse string names like 'weekly', 'biannual', and '3 quarters'
Modifies the initialize method, preserving the original string duration
# File lib/rtasklib/models.rb, line 21 def initialize input, base=nil @frozen_value = input.dup.freeze parsed = %xtask calc #{input}`.chomp super parsed, base end