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: 20171025222450_clean_up_videos.rb
    path of file: ./repos/kitsu-server/db/migrate
    
    the code of the file until where you have to start completion: class CleanUpVideos < ActiveRecord::Migration[4.2]
  def change
    change_column :videos, :embed_data, :jsonb, default: {}, using: 'embed_data::json::jsonb'
    change_column_null :videos, :created_at, false
    change_column_null :videos, :updated_at, false
    change_column_null :videos, :episode_id, false
 
    
  def change
    change_column :videos, :embed_data, :jsonb, default: {}, using: 'embed_data::json::jsonb'
    change_column_null :videos, :created_at, false
    change_column_null :videos, :updated_at, false
    change_column_null :videos, :episode_id, false
    change_column_null :videos, :streamer_id, false
    add_index :videos, :streamer_id
    add_index :videos, :sub_lang
    add_index :videos, :dub_lang
    add_index :videos, :available_regions, using: 'GIN'
  end