transformers

02af5bfa - utils: handle flash_attn missing from importlib packages_distributions without crashing (#45524)

utils: handle flash_attn missing from importlib packages_distributions without crashing (#45524) * utils: stop crashing with KeyError when flash_attn is importable but not in the distribution map is_flash_attn_2_available / _3 / _4 / _greater_or_equal do two checks: is_available, _ = _is_package_available("flash_attn", return_version=True) is_available = is_available and "flash-attn" in [ pkg.replace("_", "-") for pkg in PACKAGE_DISTRIBUTION_MAPPING["flash_attn"] ] Step 1 uses importlib.util.find_spec, which returns a spec if any "flash_attn" import is findable (an editable install, a namespace package, a bundled shim, or a stub module under another project). Step 2 then assumes that every findable import name also has an entry in importlib.metadata.packages_distributions(). That assumption does not hold. On Python 3.13 with ComfyUI setups (#45520), and in any environment where the import is resolvable via a non-pip source, packages_distributions() has no "flash_attn" key. Because the list comprehension is evaluated before the `in` operator, short-circuit evaluation of the outer `and` does not protect us - the KeyError fires during `transformers` import and takes down the whole process before any model is loaded. Swap the four raising subscripts for `.get(name, [])`. If the name is missing from the distribution map we simply conclude that the requested flash-attention flavour is not properly installed - which is the same answer is_flash_attn_*_available() would have returned anyway - instead of raising. The inner helper `_is_package_available` already wraps the same subscript in a try/except, so we are only making the outer call sites match that contract. Fixes #45520 * utils: fix same KeyError in modeling_flash_attention_utils and add regression tests Signed-off-by: say <say.apm35@gmail.com> * style: fix ruff formatting in flash_attn fix and tests Signed-off-by: Sai Asish Y <say.apm35@gmail.com> * test: move flash_attn distribution-map regression test to test_modeling_utils Signed-off-by: Sai Asish Y <say.apm35@gmail.com> * revert this * is gh alright? --------- Signed-off-by: say <say.apm35@gmail.com> Signed-off-by: Sai Asish Y <say.apm35@gmail.com> Co-authored-by: SAY-5 <SAY-5@users.noreply.github.com> Co-authored-by: vasqu <antonprogamer@gmail.com> Co-authored-by: Anton Vlasjuk <73884904+vasqu@users.noreply.github.com>