fix name error when accelerate is not available (#26278)

* fix name error when accelerate is not available

* fix `is_fsdp_available`

src/transformers/utils/import_utils.py

@@ -607,7 +607,7 @@ def is_accelerate_available(min_version: str = None):
 
 
 def is_fsdp_available(min_version: str = "1.12.0"):
-    return version.parse(_torch_version) >= version.parse(min_version)
+    return is_torch_available() and version.parse(_torch_version) >= version.parse(min_version)
 
 
 def is_optimum_available():

tests/fsdp/test_fsdp.py

@@ -79,6 +79,7 @@ if is_torch_available():
     # hack to restore original logging level pre #21700
     get_regression_trainer = partial(tests.trainer.test_trainer.get_regression_trainer, log_level="info")
 
+require_fsdp_version = require_fsdp
 if is_accelerate_available():
     from accelerate.utils.constants import (
         FSDP_PYTORCH_VERSION,