code: def write_hdf5_flag(flag, output, path=None, **kwargs):
      
      # verify path (default to flag name)
      if path is None:
          path = flag.name
      if path is None:
          raise ValueError("Cannot determine target group name for flag in HDF5 "
                           "structure, please set `name` for each flag, or "
                           "specify the ``path`` keyword when writing")
  
      return write_hdf5_dict({path: flag}, output, **kwargs)
docs: Write a `DataQualityFlag` to an HDF5 file/group