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: 20171206164713_multiple_payment_slips.rb
    path of file: ./repos/hitobito/db/migrate
    
    the code of the file until where you have to start completion: # encoding: utf-8

#  Copyright (c) 2012-2017, Jungwacht Blauring Schweiz. This file is part of
#  hitobito and licensed under the Affero G
    
  def change
    add_column :invoices, :payment_slip, :string, null: false, default: 'ch_es'
    add_column :invoices, :beneficiary, :text

    add_column :invoice_configs, :payment_slip, :string, null: false, default: 'ch_es'
    add_column :invoice_configs, :beneficiary, :text
  end