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: model.rb
    path of file: ./repos/gitlabhq/vendor/gems/devise-pbkdf2-encryptable/lib/devise/pbkdf2_encryptable
    
    the code of the file until where you have to start completion: # frozen_string_literal: true

require 'devise/strategies/database_authenticatable'

# Based on `devise-encryptable` Encryptable model
# https://github.com/heartcombo/devise-encryptable/blob/main/lib/devise/encryptable/model.rb
module Devise
  module Mo
    
        def encryptor_class
          @encryptor_class ||= case encryptor
                               when :bcrypt
                                 raise "In order to use bcrypt as encryptor, simply remove :pbkdf2_encryptable from your devise model"
                               when nil
                                 raise "You need to specify an :encryptor in Devise configuration in order to use :pbkdf2_encryptable"
                               else
                                 Devise::Pbkdf2Encryptable::Encryptors.const_get(encryptor.to_s.classify)
                               end