code: def get_categorical_feature_names(example):
    
    features = get_example_features(example)
    return sorted([
        feature_name for feature_name in features
        if features[feature_name].WhichOneof('kind') == 'bytes_list'
    ])
docs: Returns a list of feature names for byte type features.
  
    Args:
      example: An example.
  
    Returns:
      A list of categorical feature names (e.g. ['education', 'marital_status'] )