code: def loss_creator(config):
      return nn.MSELoss()
  
imports: from unittest import TestCase
  from zoo.orca.automl.model.base_pytorch_model import PytorchModelBuilder
  from torch.utils.data import Dataset, DataLoader
  import pytest
  import numpy
  import torch
  import torch.nn
label_desc: Use image node_id 7 for calling a global function with example usage: loss_creator(config) and returns: nn