code: def _read_reference_information(self):
      
      ref_lengths = {}
      ref_names = []
      for n in range(self._n_ref):
        l_name = struct.unpack('<i',self._fh.read(4))[0]
        name = self._fh.read(l_name).rstrip('\0')
        l_ref = struct.unpack('<i',self._fh.read(4))[0]
        ref_lengths[name] = l_ref
        ref_names.append(name)
      return ref_lengths, ref_names
docs: Reads the reference names and lengths