undefined method `scope' for non ActiveRecord class

I am trying to use the geocoding capabilities into a table less
model , but the method :scope is not defined ..
is there a way to include it ?

class SearchLocation
  require 'geocoder'
  include ActiveModel::Validations
  include ActiveModel::Conversion
  extend ActiveModel::Naming
  extend Geocoder::Model::ActiveRecord # extending the class w
geocoding capaibilities ( from geocoder)

  geocoded_by :address
  reverse_geocoded_by :latitude, :longitude
...

I get the error in the geocoder/stores/active_record.rb : # scope:
geocoded objects

...lib/geocoder/stores/active_record.rb

require 'geocoder/stores/base'
# Add geocoding functionality to any ActiveRecord object.
module Geocoder::Store
  module ActiveRecord
    include Base
    # Implementation of 'included' hook method.
    def self.included(base)
      base.extend ClassMethods
      base.class_eval do

        # scope: geocoded objects
        scope :geocoded, lambda { # this raises the error

any feedback welcome