code: def forward(self, x):
      x = self.pre_block(x)
      x = self.spatial_downsample(x)
      x = self.channel_downsample(x)
      identity = x
      x = self.ffn(x)
      return x + identity
  
imports: import torch.nn
  from timm.data import IMAGENET_DEFAULT_MEAN, IMAGENET_DEFAULT_STD
  from ._registry import register_model, generate_default_cfgs
  from ._builder import build_model_with_cfg
  from timm.layers import SqueezeExcite, trunc_normal_, to_ntuple, to_2tuple
  from ._manipulate import checkpoint_seq
  import torch
label_desc: Use image node_id 2 for calling the RepVitDownsample obj's underlying member method code with example usage: obj.forward(x) and returns: unknown