class_docstr: Computes and stores the average and current value.
  
  Example:
      >>> stats = AverageMeter()
      >>> acc1 = torch.tensor(0.99) # coming from K.metrics.accuracy
      >>> stats.update(acc1, n=1)  # where n is batch size usually
      >>> round(stats.avg, 2)
      0.99
code: def update(self, val: Union[float, bool, Tensor], n: int = 1) -> None:
      self.val = val
      self.sum += val * n
      self.count += n
      self._avg = self.sum / self.count
  
imports: from typing import Union
  from kornia.core import Tensor
label_desc: Use image node_id 3 for calling the AverageMeter obj's underlying member method code with example usage: obj.update(val, n) without return types