code: def my_accuracy_func(y_pred, y_true):
      y_pred = y_pred.argmax(1)
      acc_pred = (y_pred == y_true).float().mean()
      return acc_pred * 100
  
file_path: poutyne/examples/medium_post/train_with_custom_metrics.py
imports: import torch
  import torch.nn
  from torch.utils.data import random_split
  from torchvision.datasets import MNIST
  from torchvision.transforms import ToTensor
  from poutyne import Model, Metric
label_desc: Use image node_id 1 for calling a global function with example usage: my_accuracy_func(y_pred, y_true) and returns: unknown