code: def h5features_convert(self, infile):
          
          with h5py.File(infile, 'r') as f:
              groups = list(f.keys())
          for group in groups:
              self._writer.write(
                  Reader(infile, group).read(),
                  self.groupname, append=True)
docs: Convert a h5features file to the latest h5features version.