code: def fake_metric(y_hat, y):
      return (y_hat - y).mean()
  
imports: import pandas
  import torch
  from pytorch_tabular.config import DataConfig, OptimizerConfig, TrainerConfig
  from pytorch_tabular.models.category_embedding.config import CategoryEmbeddingModelConfig
  from pytorch_tabular.tabular_model import TabularModel
  from sklearn.datasets import fetch_california_housing
  from sklearn.preprocessing import PowerTransformer
label_desc: Use image node_id 1 for calling a global function with example usage: fake_metric(y_hat, y) and returns: unknown