code: def check_llm_quantization_backend_incompatibility(
      config: "ModelConfig",
  ) -> None:  # noqa: F821
      """Checks that LLM model type with quantization uses the local backend."""
      if config.model_type != MODEL_LLM:
          return
  
      if config.quantization is None:
          return
  
      backend_type = None
      if config.backend:
          backend_type = config.backend.get("type", None)
  
      # If backend was explicitly set to Ray, then we need to raise an error
      if backend_type == "ray":
          raise ConfigValidationError(
              f"LLM with quantization requires the 'local' backend, found: '{backend_type}'"
          )
  
      # If the backend is not explicitly set, then we need to check if a Ray process is running
      # If a Ray process is running, then we need to raise an error because the backend will be set to Ray
      if config.backend is None:
          try:
              # May not be installed, so we need to catch the ImportError
              import ray
  
              if ray.is_initialized():
                  raise ConfigValidationError(
                      "LLM with quantization requires the 'local' backend, but backend will be set "
                      "to Ray since Ray is already running locally."
                  )
          except ImportError:
              pass
  
imports: from abc import ABC, abstractmethod
  from re import findall
  from typing import Callable, TYPE_CHECKING
  from transformers import AutoConfig
  from ludwig.api_annotations import DeveloperAPI
  from ludwig.constants import AUDIO, BINARY, CATEGORY, IMAGE, IN_MEMORY, MIN_QUANTIZATION_BITS_FOR_MERGE_AND_UNLOAD, MODEL_ECD, MODEL_GBM, MODEL_LLM, NUMBER, SEQUENCE, SET, TEXT, TIMESERIES, VECTOR
  from ludwig.error import ConfigValidationError
  from ludwig.utils.metric_utils import get_feature_to_metric_names_map_from_feature_collection
  from ludwig.utils.misc_utils import merge_dict
label_desc: Use image node_id 31 for calling a global function with example usage: check_llm_quantization_backend_incompatibility(config) without return types