lazy import

Signed-off-by: youkaichao <youkaichao@gmail.com>

vllm/distributed/parallel_state.py

@@ -39,7 +39,6 @@
 import vllm.envs as envs
 from vllm.distributed.utils import StatelessProcessGroup
 from vllm.logger import init_logger
-from vllm.platforms import current_platform
 from vllm.utils import direct_register_custom_op, supports_custom_op
 
 if TYPE_CHECKING:
@@ -194,6 +193,7 @@ def __init__(
         assert self.cpu_group is not None
         assert self.device_group is not None
 
+        from vllm.platforms import current_platform
         if current_platform.is_cuda_alike():
             self.device = torch.device(f"cuda:{local_rank}")
         else:
@@ -1188,6 +1188,7 @@ def cleanup_dist_env_and_memory(shutdown_ray: bool = False):
         import ray  # Lazy import Ray
         ray.shutdown()
     gc.collect()
+    from vllm.platforms import current_platform
     if not current_platform.is_cpu():
         torch.cuda.empty_cache()