Allow loading tasks without downloading split files

[mfeurer]

similar to how this is done for datasets, where one can disable downloading the dataset arff file.

[OmarAI2003]

I'm interested in this issue and plan to explore it in the coming days.

[OmarAI2003]

Hi @mfeurer! 👋

I analyzed the codebase and found that download_splits parameter already exists in method get_task(), and defaults to false in this PR #1345 in commit 2581671 by @PGijsbers

Should this issue be considered as completed, or is there additional work needed to provide some true lazy loading?

The only thing I noticed is that the method get_train_test_split_indices (line 154)

openml-python/openml/tasks/task.py

Line 154 in 4b1bdf4

def get_train_test_split_indices(

, downloads split files automatically; it doesn't respect the user's intent to avoid downloading splits and will fetch them even when download_splits=False.