code: def test_register_nan():
      reporter = Reporter()
      with reporter.observe("train", 1) as sub:
          sub.register({"a": np.nan}, weight=1.0)
          sub.next()
  
imports: import logging
  import uuid
  from pathlib import Path
  import numpy
  import pytest
  import torch
  from torch.utils.tensorboard import SummaryWriter
  from espnet2.train.reporter import Average, ReportedValue, Reporter, aggregate
label_desc: Use image node_id 23 for calling a global function with example usage: test_register_nan() without return types