code: def query_versions(self, version=None):
          
          if version not in RELEASE_AND_CANDIDATE_LATEST_VERSIONS:
              return [version]
  
          url = urljoin(self.base_url, 'releases/')
          parser = self._create_directory_parser(url)
          if version:
              versions = parser.filter(RELEASE_AND_CANDIDATE_LATEST_VERSIONS[version])
              from distutils.version import LooseVersion
              versions.sort(key=LooseVersion)
              return [versions[-1]]
          else:
              return parser.entries
docs: Check specified version and resolve special values.