[Feature]: Lazy import DeepseekV32IndexerCache

[noooop]

🚀 The feature, motivation and pitch

I need to manually downgrade transformers to test some models, such as Qwen/Qwen2.5-Math-PRM-7B, which requires transformers==4.53.2

It's great if lazy import DeepseekV32IndexerCache, so I don't have to comment out these codes every time.

vllm/vllm/v1/worker/gpu_model_runner.py

Line 50 in 7e6edb1

from vllm.model_executor.models.deepseek_v2 import DeepseekV32IndexerCache

vllm/vllm/v1/spec_decode/eagle.py

Line 23 in 7e6edb1

from vllm.model_executor.models.deepseek_v2 import DeepseekV32IndexerCache

vllm/vllm/v1/worker/gpu_model_runner.py

Lines 4683 to 4687 in 7e6edb1

	ds_indexer_layers = get_layers_from_vllm_config(
	self.vllm_config, DeepseekV32IndexerCache
	)
	for layer_name, ds_indexer_module in ds_indexer_layers.items():
	kv_cache_spec[layer_name] = ds_indexer_module.get_kv_cache_spec()

Reproduce code

pip install transformers==4.53.2
pytest -s -vvv tests/models/language/pooling/test_reward.py

cc @heheda12345

Alternatives

No response

Additional context

No response

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[DarkLight1337]

I ran into this issue when developing #26792 😅

That being said, officially the min transformers version is now 4.55.2. Nevertheless, to avoid unnecessary dependencies, we should not import specific modeling files directly inside GPU model runner.

[DarkLight1337]

cc @WoosukKwon @heheda12345 any thoughts on this?

[noooop]

Nevertheless, to avoid unnecessary dependencies, we should not import specific modeling files directly inside GPU model runner.

+1

[noooop]

Qwen/Qwen2.5-Math-PRM-7B is currently the only StepPooler test case, so a downgrade test is needed. 😅

[heheda12345]

The gpu model runner has been fixed by #26587.
@luccafong can you help to cleanup the eagle.py?