docstr: Update center used for teacher output.
docstr_tok: ["Update","center","used","for","teacher","output","."]
code: def update_center(self, teacher_output):
      """
      Update center used for teacher output.
      """
      batch_center = torch.sum(teacher_output, dim=0, keepdim=True)
      torch.distributed.all_reduce(batch_center)
      batch_center = batch_center / (
          len(teacher_output) * torch.distributed.get_world_size()
      )
      self.center = (
          self.center * self.center_momentum
          + batch_center * (1 - self.center_momentum)
      )
  
imports: import math
  import apex
  import einops
  import torch
  import numpy
  import torch.nn.functional
  from torch.nn.init import trunc_normal_
  from megatron import get_args, print_rank_0
  from megatron.model.utils import get_linear_layer
  from megatron.model.vision.vit_backbone import VitBackbone
  from megatron.model.module import MegatronModule
  from megatron.model.vision.mit_backbone import mit_b5_avg
  from megatron.model.vision.esvit_swin_backbone import get_swin
label_desc: Use image node_id 3 for calling the DINOLoss obj's underlying member method code with example usage: obj.update_center(teacher_output) without return types