Inherit initialize() method in ruby?

I still can't figure out how to make a subclass constructor follow its parent...
example:

require 'mechanize'

class Scraper
    attr_accessor :agent

    def initialize 
    # I dont know if using instance variable is the right thing to do
    @agent = Mechanize.new 
    end
end

class ScraperA < Scraper
end

I want to make ScraperA follow its parent constructor behaviour,
that is instantiate a Mechanize object without me retyping Mechanize.new in ScraperA initialize() method. Is this possible ?

Just want to follow DRY principle but ruby makes it hard for me ???
Hope not, maybe it's just my ignorance. Looking forward for simple solution,Tnx.

Edit:
it turns out that I had empty initialize() method in ScraperA, which override the default initialize(). So yeah the example is working, because no empty initialize method there. Sorry for my stupidity. Tnx.