code: def reset_classifier(self, num_classes, global_pool=None):
      self.num_classes = num_classes
      if global_pool is not None:
          assert global_pool in ("avg", "")
          self.global_pool = global_pool
      self.head = (
          nn.Linear(self.embed_dim, num_classes)
          if num_classes > 0
          else nn.Identity()
      )
  
imports: import math
  from typing import Tuple, List, Callable, Union
  import torch
  import torch.nn
  import torch.nn.functional
  import torch.utils.checkpoint
  from timm.data import IMAGENET_DEFAULT_MEAN, IMAGENET_DEFAULT_STD
  from timm.layers import DropPath, to_2tuple, to_ntuple, trunc_normal_, LayerNorm, use_fused_attn
  from ._builder import build_model_with_cfg
  from ._registry import register_model, generate_default_cfgs
label_desc: Use image node_id 8 for calling the PyramidVisionTransformerV2 obj's underlying member method code with example usage: obj.reset_classifier(num_classes, global_pool) without return types