class_docstr: ClassBlock
class_docstr_tok: ["ClassBlock"]
code: def forward(self, x):
      cls_embed = x[:, :1]
      cls_embed = cls_embed + self.attn(self.norm1(x))
      cls_embed = cls_embed + self.mlp(self.norm2(cls_embed))
      return torch.cat([cls_embed, x[:, 1:]], dim=1)
  
imports: import torch
  from torch import nn
  from timm.models.layers import DropPath
  import numpy
  from towhee.models.wave_vit.wave_vit_utils import DWT2D, IDWT2D
  from towhee.models.utils.init_vit_weights import init_vit_weights
  from towhee.models.layers.mlp import Mlp
label_desc: Use image node_id 2 for calling the ClassBlock obj's underlying member method code with example usage: obj.forward(x) and returns: torch