class_docstr: Config object used to define a deep learning (pytorch) model.
code: def loss_fn(self) -> LossFunction:
      return self._loss_fn
  
imports: import io
  import json
  import copy
  import logging
  from typing import List, Optional, Tuple, Union
  import numpy
  import pandas
  from scipy.stats import norm
  from abc import abstractmethod
  from enum import Enum
  from merlion.models.base import Config, ModelBase
  from merlion.plot import Figure
  from merlion.transform.base import TransformBase, Identity
  from merlion.transform.factory import TransformFactory
  from merlion.utils.misc import initializer
  from merlion.utils.time_series import to_pd_datetime, to_timestamp, TimeSeries, AggregationPolicy, MissingValuePolicy
label_desc: Use image node_id 4 for calling the DeepConfig obj's underlying member method code with example usage: obj.loss_fn() and returns: self