initalize clebsch_gordan submodule in rascaline.torch

python/rascaline-torch/rascaline/torch/utils/__init__.py

@@ -1,6 +1,7 @@
 import os
 
 from .power_spectrum import PowerSpectrum
+from . import clebsch_gordan
 
 
 _HERE = os.path.dirname(__file__)
@@ -10,4 +11,4 @@
 Path containing the CMake configuration files for the underlying C library
 """
 
-__all__ = ["PowerSpectrum"]
+__all__ = ["PowerSpectrum", "clebsch_gordan"]

python/rascaline-torch/rascaline/torch/utils/clebsch_gordan.py

@@ -0,0 +1,39 @@
+import importlib
+import sys
+from typing import List, Optional, Union
+
+import torch
+from metatensor.torch import Labels, TensorBlock, TensorMap
+
+import rascaline.utils.clebsch_gordan
+
+
+# For details what is happening here take a look an `rascaline.torch.calculators`.
+
+# Step 1: create te `_classes` module as an empty module
+spec = importlib.util.spec_from_loader(
+    "rascaline.torch.utils.clebsch_gordan._classes",
+    loader=None,
+)
+module = importlib.util.module_from_spec(spec)
+# This module only exposes a handful of things, defined here. Any changes here MUST also
+# be made to the `metatensor/operations/_classes.py` file, which is used in non
+# TorchScript mode.
+module.__dict__["Labels"] = Labels
+module.__dict__["TensorBlock"] = TensorBlock
+module.__dict__["TensorMap"] = TensorMap
+
+# register the module in sys.modules, so future import find it directly
+sys.modules[spec.name] = module
+
+
+# Step 2: create a module named `rascaline.torch.utils.clebsch_gordan` using code from
+# `rascaline.utils.clebsch_gordan`
+spec = importlib.util.spec_from_file_location(
+    "rascaline.torch.utils.clebsch_gordan",
+    rascaline.utils.clebsch_gordan.__file__,
+)
+
+module = importlib.util.module_from_spec(spec)
+sys.modules[spec.name] = module
+spec.loader.exec_module(module)