lookup (I18n::Backend::Simple)

    # File lib/active_support/vendor/i18n-0.0.1/i18n/backend/simple.rb, line 92
            def lookup(locale, key, scope = [])
              return unless key
              init_translations unless initialized?
              keys = I18n.send(:normalize_translation_keys, locale, key, scope)
              keys.inject(translations) do |result, k|
                if (x = result[k.to_sym]).nil?
                  return nil
                else
                  x
                end
              end
            end