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: 20190724000001_rename_reserved_words.rb
    path of file: ./repos/zammad/db/migrate
    
    the code of the file until where you have to start completion: # Copyright (C) 2012-2024 Zammad Foundation, https://zammad-foundation.org/

class RenameReservedWords < ActiveRecord::Migration[5.1]
  def up
    return if !Setting.exists?(name: 'system_init_done')

    models = ObjectManager.list_objects.map(&:underscore).map { |object| object.tr('_', '/') }.map { |x| x.classify.constantize }

    reserved_words = %w[url icon initials avatar permission validate subscribe unsubscribe translate search]
    models.each do |model|

      reserved_words.each do |reserved_word|

        next if ActiveRecord::Base.connection.columns(model.table_name).map(&:name).exclude?(reserved_word)

        sanitized_name = "_#
    
  def up
    return if !Setting.exists?(name: 'system_init_done')

    models = ObjectManager.list_objects.map(&:underscore).map { |object| object.tr('_', '/') }.map { |x| x.classify.constantize }

    reserved_words = %w[url icon initials avatar permission validate subscribe unsubscribe translate search]
    models.each do |model|

      reserved_words.each do |reserved_word|

        next if ActiveRecord::Base.connection.columns(model.table_name).map(&:name).exclude?(reserved_word)

        sanitized_name = "_#{reserved_word}"

        ActiveRecord::Migration.rename_column(model.table_name.to_sym, reserved_word.to_sym, sanitized_name.to_sym)
        model.reset_column_information

        attribute = ObjectManager::Attribute.get(
          object: model.to_app_model,
          name:   reserved_word,
        )
        next if !attribute

        attribute.update!(name: sanitized_name)
      end
    end
  end