Add OSFDownloadMixin

Mirrors OhanaDownloadMixin (ensure_file, prefetch_files, manifest, retries)
for datasets hosted on the Open Science Framework. Public OSF projects
need no auth; OSF_TOKEN env var supported for private projects.

Multi-component projects (OSF storage caps at ~50 GB per node) are
supported via OSF_PROJECT_FALLBACKS — the manifest aggregates files
across all configured nodes with the primary winning on duplicates.
Used by the upcoming MEG-MASC dataset, which spans four sibling nodes
(ag3kj, h2tzn, u5327, dr4wy).

Author: Gereon Elvers

pnpl/datasets/mixins/__init__.py

@@ -13,6 +13,7 @@
 
 from .download import HFDownloadMixin
 from .ohana_download import OhanaDownloadMixin
+from .osf_download import OSFDownloadMixin
 from .standardization import StandardizationMixin
 from .continuous_h5 import ContinuousH5Mixin
 from .epoched_h5 import EpochedH5Mixin
@@ -21,6 +22,7 @@
 __all__ = [
     "HFDownloadMixin",
     "OhanaDownloadMixin",
+    "OSFDownloadMixin",
     "StandardizationMixin",
     "ContinuousH5Mixin",
     "EpochedH5Mixin",