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: pay_helper.rb
    path of file: ./repos/railsdevs.com/test/support/helpers
    
    the code of the file until where you have to start completion: module PayHelper
  extend ActiveSupport::Concern

  included do
    def stub_pay(user, plan_price_id: part_time_plan_price_id)
      checkout = Minitest::Mock.new
      checkout.expect(:url, "checkout.stripe.com")

      payment_processor = Minitest::Mock.new
      payment_processor.expect(:checkout, checkout) do |options|
        options[:mode] == "subscription" &&
          options[:line_items] == plan_price_id
     
    
    def stub_pay(user, plan_price_id: part_time_plan_price_id)
      checkout = Minitest::Mock.new
      checkout.expect(:url, "checkout.stripe.com")

      payment_processor = Minitest::Mock.new
      payment_processor.expect(:checkout, checkout) do |options|
        options[:mode] == "subscription" &&
          options[:line_items] == plan_price_id
      end

      user.stub(:payment_processor, payment_processor) do
        yield
      end

      checkout.verify
      payment_processor.verify
    end