# File lib/pickle/session.rb, line 144
    def convert_models_to_attributes(ar_class, attrs)
      attrs.each do |key, val|
        if val.is_a?(ActiveRecord::Base) && ar_class.column_names.include?("#{key}_id")
          attrs["#{key}_id"] = val.id
          attrs["#{key}_type"] = val.class.base_class.name if ar_class.column_names.include?("#{key}_type")
          attrs.delete(key)
        end
      end
    end