在ruby中解析2020-W9日期的好方法是什么？

require 'date'

def parse_date(date_str)
  year, week = date_str.scan(/\d+/)
  start_of_week = Date.commercial(year.to_i, week.to_i)
  end_of_week = start_of_week + 6
  return start_of_week, end_of_week
end

start_date, end_date = parse_date('2020-W9')
puts "Start date: #{start_date}"
puts "End date: #{end_date}"