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: omniauth_callbacks_controller.rb
    path of file: ./repos/devise/app/controllers/devise
    
    the code of the file until where you have to start completion: # frozen_string_literal: true

class Devise::OmniauthCallbacksController < DeviseController
  prepend_before_action { request.env["devise.skip
    
  def failure_message
    exception = request.respond_to?(:get_header) ? request.get_header("omniauth.error") : request.env["omniauth.error"]
    error   = exception.error_reason if exception.respond_to?(:error_reason)
    error ||= exception.error        if exception.respond_to?(:error)
    error ||= (request.respond_to?(:get_header) ? request.get_header("omniauth.error.type") : request.env["omniauth.error.type"]).to_s
    error.to_s.humanize if error
  end