third party helper module (newbie)

Hello everybody,

I found a cool helper for generating dependant select controls by
Dimitrij Denissenko, which I don't quite know how to install it. The
structure of the helper is as follows:

module ActionView
  module Helpers
    module RelatedSelectFormOptionsHelper

So, I tried to stick it in my app/helpers and do
"helper :related_select_form_options" in a controller, which produces
exactly this: "app/helpers/related_select_form_options_helper.rb to
define RelatedSelectFormOptionsHelper"

If I put the thing into the site helpers directory, I get "couldn't
find related_select_form_options_helper.rb".

So, I don't quite know how to proceed from here. What's the best way
to do it?

Solved. Hope it will help somebody. Basically, after some extensive research I found out that the way to do it is to put the code in a file and then “require” it from environment.rb. Found the answer here:
in the comments section. Kudos to evansj who wrote the comment.