code: def check_tied_features_valid(
      config: "ModelConfig",
  ) -> None:  # noqa: F821
      """Checks that all tied features are valid."""
      input_features = config.input_features
      input_feature_names = {
          input_feature.name for input_feature in input_features
      }
  
      for input_feature in input_features:
          if (
              input_feature.tied
              and input_feature.tied not in input_feature_names
          ):
              raise ConfigValidationError(
                  f"Feature {input_feature.name} is tied to feature {input_feature.tied}, but the "
                  f"'{input_feature.tied}' feature does not exist."
              )
  
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 4 for calling a global function with example usage: check_tied_features_valid(config) without return types