Fix circle reference which cause tpu_platform failed to import

[mrjunwan-lang]

Description

Fix circle reference which cause tpu_platform failed to import.

before the fix:
Traceback (most recent call last):
File "", line 1, in
File "/home/mrjunwan_google_com/tpu-inference/tpu_inference/platforms/init.py", line 2, in
from tpu_inference.platforms.tpu_platform import TpuPlatform
File "/home/mrjunwan_google_com/tpu-inference/tpu_inference/platforms/tpu_platform.py", line 11, in
from vllm.sampling_params import SamplingParams, SamplingType
File "/home/mrjunwan_google_com/vllm/vllm/sampling_params.py", line 15, in
from vllm.logits_process import LogitsProcessor
File "/home/mrjunwan_google_com/vllm/vllm/logits_process.py", line 8, in
from vllm.tokenizers import TokenizerLike
File "/home/mrjunwan_google_com/vllm/vllm/tokenizers/init.py", line 4, in
from .deepseekv32 import DeepseekV32Tokenizer
File "/home/mrjunwan_google_com/vllm/vllm/tokenizers/deepseekv32.py", line 9, in
from .hf import HfTokenizer, TokenizerLike
File "/home/mrjunwan_google_com/vllm/vllm/tokenizers/hf.py", line 10, in
from vllm.transformers_utils.config import get_sentence_transformer_tokenizer_config
File "/home/mrjunwan_google_com/vllm/vllm/transformers_utils/config.py", line 28, in
from vllm.config.utils import getattr_iter
File "/home/mrjunwan_google_com/vllm/vllm/config/init.py", line 17, in
from vllm.config.model import (
File "/home/mrjunwan_google_com/vllm/vllm/config/model.py", line 24, in
from vllm.transformers_utils.config import (
ImportError: cannot import name 'ConfigFormat' from partially initialized module 'vllm.transformers_utils.config' (most likely due to a circular import) (/home/mrjunwan_google_com/vllm/vllm/transformers_utils/config.py)

after the fix:
python examples/offline_inference.py
--model=Qwen/Qwen3-0.6B
--tensor_parallel_size=4
--data_parallel_size=1
--max_model_len=1024
run successfully

[github-actions]

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