def split_parts_and_interval(expression_str)
      interval = nil
      parts = expression_str.split(/ +/).map do |part|
        part, part_interval = part.split('/')
        interval = part_interval unless part_interval.blank?
        next nil if part.blank? || part == '*'

        part
      end

      [parts, interval]
    end
def split_parts_and_interval(expression_str)
      interval = nil
      parts = expression_str.split(/ +/).map do |part|
        part, part_interval = part.split('/')
        interval = part_interval unless part_interval.blank?
        next nil if part.blank? || part == '*'

        part
      end

      [parts, interval]
    end
Split a cron string and extract the LAST interval that appears