You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: railtie.rb
    path of file: ./repos/warden-github-rails/lib/warden/github/rails
    
    the code of the file until where you have to start completion: module Warden
  module GitHub
    module Rails
      class Railtie < ::Rails::Railtie
        SERIALIZE_FROM_SESSION = -> ((class_name, data)) do
          class_name.constantize.new.tap { |user| user.marshal_loa
    
        def setup_scopes(config)
          Rails.scopes.each do |scope, scope_config|
            config.scope_defaults scope, strategies: [:github],
                                         config: scope_config
            config.serialize_from_session(scope, &SERIALIZE_FROM_SESSION)
            config.serialize_into_session(scope, &SERIALIZE_INTO_SESSION)
          end
        end