Add from __future__ import annotations

phono3py/cui/triplets_info.py

@@ -34,8 +34,9 @@
 # ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 # POSSIBILITY OF SUCH DAMAGE.
 
-from collections.abc import Sequence
-from typing import Optional, Union
+from __future__ import annotations
+
+import os
 
 import numpy as np
 from numpy.typing import ArrayLike
@@ -49,13 +50,13 @@ from phono3py.phonon3.triplets import get_triplets_at_q
 def write_grid_points(
     primitive: PhonopyAtoms,
     bz_grid: BZGrid,
-    band_indices: Optional[Union[Sequence, np.ndarray]] = None,
-    sigmas: Optional[Union[Sequence, np.ndarray]] = None,
-    temperatures: Optional[Union[Sequence, np.ndarray]] = None,
+    band_indices: ArrayLike | None = None,
+    sigmas: ArrayLike | None = None,
+    temperatures: ArrayLike | None = None,
     is_kappa_star: bool = True,
     is_lbte: bool = False,
-    compression: Union[str, int] = "gzip",
-    filename: bool = None,
+    compression: str | int = "gzip",
+    filename: str | os.PathLike | None = None,
 ):
     """Write grid points into files."""
     ir_grid_points, ir_grid_weights = _get_ir_grid_points(

phono3py/file_IO.py

@@ -54,6 +54,7 @@ from phonopy.file_IO import (
     write_FORCE_SETS,
 )
 
+from phono3py.phonon.grid import BZGrid
 from phono3py.version import __version__
 
 
@@ -483,9 +484,9 @@ def write_grid_address_to_hdf5(
     grid_address,
     mesh,
     grid_mapping_table,
-    bz_grid=None,
-    compression: Union[str, int] = "gzip",
-    filename=None,
+    bz_grid: BZGrid | None = None,
+    compression: str | int = "gzip",
+    filename: str | os.PathLike | None = None,
 ):
     """Write grid addresses to grid_address.hdf5."""
     suffix = _get_filename_suffix(mesh, filename=filename)