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: 20171006132129_create_delayed_jobs.rb
    path of file: ./repos/bugsnag-ruby/example/rails-42/db/migrate
    
    the code of the file until where you have to start completion: class CreateDelayedJobs < ActiveRecord::Migration
  def self.up
    create_table :delayed_jobs, force: true do |table|
      table.integer :priority, default: 0, null: false # Allows some jobs to jump to the front of the queue
      table.integer :attempts, default: 0, null: false # Provides for retries, but still fail eventually.
      table.text :handler,                 null: false # YAML-encoded string of the object that will do work
      table.text :last_error                           # reason for last failure (See Note below)
      table.datetime :run_at                           # When to run. Could be Time.zone.now for immediately, or sometime in the future.
      table.datetime :locked_at                        # Set when a client is working on this object
      table.datetime :failed_at                        # Set when all retries have failed (actually, by default, the record is deleted instead)
      table.string :locked_by                          # Who is working on this object (if locked)
      table.string :queue                              # The name of the queue
    
  def self.up
    create_table :delayed_jobs, force: true do |table|
      table.integer :priority, default: 0, null: false # Allows some jobs to jump to the front of the queue
      table.integer :attempts, default: 0, null: false # Provides for retries, but still fail eventually.
      table.text :handler,                 null: false # YAML-encoded string of the object that will do work
      table.text :last_error                           # reason for last failure (See Note below)
      table.datetime :run_at                           # When to run. Could be Time.zone.now for immediately, or sometime in the future.
      table.datetime :locked_at                        # Set when a client is working on this object
      table.datetime :failed_at                        # Set when all retries have failed (actually, by default, the record is deleted instead)
      table.string :locked_by                          # Who is working on this object (if locked)
      table.string :queue                              # The name of the queue this job is in
      table.timestamps null: true
    end

    add_index :delayed_jobs, [:priority, :run_at], name: "delayed_jobs_priority"
  end

  def self.down
    drop_table :delayed_jobs
  end
end