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: 20101026184950_rename_columns_for_devise.rb
    path of file: ./repos/spree_auth_devise/db/migrate
    
    the code of the file until where you have to start completion: class RenameColumnsForDevise < SpreeExtension::Migration[4.2]
  def up
    return if column_exists?(:spree_users, :password_salt)
    rename_column :spree_users, :crypted_password, :encrypted_password
    rename_column :spree_users, :salt, :password_salt
    rename_column :spree_users, :remember_token_expires_at, :remember_created_at
    rename_column :
    
  def down
    remove_column :spree_users, :authentication_token
    remove_column :spree_users, :locked_at
    remove_column :spree_users, :unlock_token
    rename_column :spree_users, :last_sign_in_ip, :last_login_ip
    rename_column :spree_users, :current_sign_in_ip, :current_login_ip
    rename_column :spree_users, :last_sign_in_at, :last_login_at
    rename_column :spree_users, :current_sign_in_at, :current_login_at
    rename_column :spree_users, :reset_password_token, :single_access_token
    rename_column :spree_users, :failed_attempts, :failed_login_count
    rename_column :spree_users, :sign_in_count, :login_count
    rename_column :spree_users, :remember_created_at, :remember_token_expires_at
    rename_column :spree_users, :password_salt, :salt
    rename_column :spree_users, :encrypted_password, :crypted_password
    add_column :spree_users, :unlock_token, :string
    add_column :spree_users, :openid_identifier, :string
  end