code: def _str_desc(self, reader):
          
          data_version = reader.data_version
          if data_version is not None:
              data_version = data_version.replace("releases/", "")
          desc = "{OBO}: fmt({FMT}) rel({REL}) {N:,} GO Terms".format(
              OBO=reader.obo_file, FMT=reader.format_version,
              REL=data_version, N=len(self))
          if reader.optobj:
              desc = "{D}; optional_attrs({A})".format(D=desc, A=" ".join(sorted(reader.optobj.optional_attrs)))
          return desc
docs: String containing information about the current GO DAG.