gnu: Add python-pytorch-lightning.

* gnu/packages/machine-learning.scm (python-pytorch-lightning): New variable.

gnu/packages/machine-learning.scm

@@ -102,6 +102,7 @@
   #:use-module (gnu packages statistics)
   #:use-module (gnu packages sqlite)
   #:use-module (gnu packages swig)
+  #:use-module (gnu packages time)
   #:use-module (gnu packages tls)
   #:use-module (gnu packages video)
   #:use-module (gnu packages web)
@@ -3518,6 +3519,128 @@ validating answers, managing hierarchical prompts and providing error
 feedback.")
     (license license:expat)))
 
+(define-public python-pytorch-lightning
+  (package
+    (name "python-pytorch-lightning")
+    (version "2.0.2")
+    (source (origin
+              (method git-fetch)
+              (uri (git-reference
+                    (url "https://github.com/Lightning-AI/lightning")
+                    (commit version)))
+              (file-name (git-file-name name version))
+              (sha256
+               (base32
+                "1w4lajiql4y5nnhqf6i5wii1mrwnhp5f4bzbwdzb5zz0d0lysb1i"))))
+    (build-system pyproject-build-system)
+    (arguments
+     (list
+      #:test-flags
+      '(list "-m" "not cloud and not tpu" "tests/tests_pytorch"
+             ;; we don't have onnxruntime
+             "--ignore=tests/tests_pytorch/models/test_onnx.py"
+
+             ;; We don't have tensorboard, so we skip all those tests that
+             ;; require it for logging.
+             "--ignore=tests/tests_pytorch/checkpointing/test_model_checkpoint.py"
+             "--ignore=tests/tests_pytorch/loggers/test_all.py"
+             "--ignore=tests/tests_pytorch/loggers/test_logger.py"
+             "--ignore=tests/tests_pytorch/loggers/test_tensorboard.py"
+             "--ignore=tests/tests_pytorch/models/test_cpu.py"
+             "--ignore=tests/tests_pytorch/models/test_hparams.py"
+             "--ignore=tests/tests_pytorch/models/test_restore.py"
+             "--ignore=tests/tests_pytorch/profilers/test_profiler.py"
+             "--ignore=tests/tests_pytorch/trainer/flags/test_fast_dev_run.py"
+             "--ignore=tests/tests_pytorch/trainer/logging_/test_eval_loop_logging.py"
+             "--ignore=tests/tests_pytorch/trainer/logging_/test_train_loop_logging.py"
+             "--ignore=tests/tests_pytorch/trainer/properties/test_loggers.py"
+             "--ignore=tests/tests_pytorch/trainer/properties/test_log_dir.py"
+             "--ignore=tests/tests_pytorch/trainer/test_trainer.py"
+
+             ;; This needs internet access
+             "--ignore=tests/tests_pytorch/helpers/test_models.py"
+             "--ignore=tests/tests_pytorch/helpers/test_datasets.py"
+             "--ignore=tests/tests_pytorch/helpers/datasets.py"
+
+             ;; We have no legacy checkpoints
+             "--ignore=tests/tests_pytorch/checkpointing/test_legacy_checkpoints.py"
+
+             ;; TypeError: _FlakyPlugin._make_test_flaky() got an unexpected keyword argument 'reruns'
+             "--ignore=tests/tests_pytorch/models/test_amp.py"
+             "--ignore=tests/tests_pytorch/profilers/test_profiler.py"
+
+             "--ignore=tests/tests_pytorch/graveyard/test_legacy_import_unpickler.py"
+
+             "-k"
+             (string-append
+              ;; We don't have tensorboard
+              "not test_property_logger"
+              " and not test_cli_logger_shorthand"
+              ;; Something wrong with Flaky
+              " and not test_servable_module_validator_with_trainer"))
+      #:phases
+      '(modify-phases %standard-phases
+         (add-after 'unpack 'patch-version-detection
+           (lambda _
+             ;; We do have pytorch 1.13.1, but the version comparison fails.
+             (substitute* "src/lightning/fabric/utilities/imports.py"
+               (("_TORCH_GREATER_EQUAL_1_13 =.*")
+                "_TORCH_GREATER_EQUAL_1_13 = True\n"))))
+         (add-before 'build 'pre-build
+           (lambda _ (setenv "PACKAGE_NAME" "lightning")))
+         (add-after 'install 'pre-build-pytorch
+           (lambda _
+             ;; pyproject-build-system only tolerates unicycles.
+             (for-each delete-file (find-files "dist" "\\.whl"))
+             (setenv "PACKAGE_NAME" "pytorch")))
+         (add-after 'pre-build-pytorch 'build-pytorch
+           (assoc-ref %standard-phases 'build))
+         (add-after 'build-pytorch 'install-pytorch
+           (assoc-ref %standard-phases 'install))
+         (add-before 'check 'pre-check
+           (lambda _
+             ;; We don't have Tensorboard
+             (substitute* "tests/tests_pytorch/test_cli.py"
+               ((" TensorBoardLogger\\(\".\"\\)") "")))))))
+    (propagated-inputs
+     (list python-arrow
+           python-beautifulsoup4
+           python-croniter
+           python-dateutils
+           python-deepdiff
+           python-fastapi-for-pytorch-lightning
+           python-fsspec
+           python-inquirer
+           python-jsonargparse
+           python-lightning-cloud
+           python-lightning-utilities
+           python-numpy
+           python-packaging
+           python-pytorch
+           python-pyyaml
+           python-starsessions-for-pytorch-lightning
+           python-torchmetrics
+           python-torchvision
+           python-tqdm
+           python-traitlets
+           python-typing-extensions))
+    (native-inputs
+     (list python-aiohttp
+           python-cloudpickle
+           python-coverage
+           python-flaky
+           python-pympler
+           python-pytest
+           python-psutil
+           python-requests-mock
+           python-scikit-learn))
+    (home-page "https://lightning.ai/")
+    (synopsis "Deep learning framework to train, deploy, and ship AI products")
+    (description
+     "PyTorch Lightning is just organized PyTorch; Lightning disentangles
+PyTorch code to decouple the science from the engineering.")
+    (license license:asl2.0)))
+
 (define-public python-torchmetrics
   (package
     (name "python-torchmetrics")