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: 20220223222236_add_service_name_to_active_storage_blobs.active_storage.rb
    path of file: ./repos/rails_new/db/migrate
    
    the code of the file until where you have to start completion: # This migration comes from active_storage (originally 20190112182829)
cl
    
  def up
    unless column_exists?(:active_storage_blobs, :service_name)
      add_column :active_storage_blobs, :service_name, :string

      if configured_service = ActiveStorage::Blob.service.name
        ActiveStorage::Blob.unscoped.update_all(service_name: configured_service)
      end