def pre_save(options = { mapping: :_default })
      xml = super(options)
      xml.add_namespace('http://www.sitemaps.org/schemas/sitemap/0.9')
      xml.add_namespace('rs', 'http://www.openarchives.org/rs/terms/')
      xml
    end
def pre_save(options = { mapping: :_default })
      xml = super(options)
      xml.add_namespace('http://www.sitemaps.org/schemas/sitemap/0.9')
      xml.add_namespace('rs', 'http://www.openarchives.org/rs/terms/')
      xml
    end
------------------------------------------------------------
 Overrides
 Overrides +::XML::Mapping.pre_save+ to declare the Sitemap and ResourceSync namespaces.
 Used for writing.