chore: import upstream snapshot with attribution

python/ray/train/torch/__init__.py

@@ -0,0 +1,54 @@
+# isort: off
+try:
+    import torch  # noqa: F401
+except ModuleNotFoundError:
+    raise ModuleNotFoundError(
+        "PyTorch isn't installed. To install PyTorch, run 'pip install torch'"
+    )
+# isort: on
+
+from ray.train.torch.config import TorchConfig
+from ray.train.torch.torch_checkpoint import TorchCheckpoint
+from ray.train.torch.torch_trainer import TorchTrainer
+from ray.train.torch.train_loop_utils import (
+    accelerate,
+    backward,
+    enable_reproducibility,
+    get_device,
+    get_devices,
+    prepare_data_loader,
+    prepare_model,
+    prepare_optimizer,
+)
+from ray.train.v2._internal.constants import is_v2_enabled
+
+if is_v2_enabled():
+    from ray.train.v2.torch.torch_trainer import TorchTrainer  # noqa: F811
+    from ray.train.v2.torch.train_loop_utils import (  # noqa: F811
+        accelerate,
+        backward,
+        enable_reproducibility,
+        get_device,
+        get_devices,
+        prepare_data_loader,
+        prepare_model,
+        prepare_optimizer,
+    )
+
+
+__all__ = [
+    "TorchTrainer",
+    "TorchCheckpoint",
+    "TorchConfig",
+    "accelerate",
+    "get_device",
+    "get_devices",
+    "prepare_model",
+    "prepare_optimizer",
+    "prepare_data_loader",
+    "backward",
+    "enable_reproducibility",
+]
+
+
+# DO NOT ADD ANYTHING AFTER THIS LINE.