code: def forward(self, x):
      x = self.forward_features(x)
      return x
  
imports: import math
  from functools import partial
  from typing import Optional
  import torch
  import torch.nn
  from pytorch_toolbelt.modules.interfaces import AbstractEncoder, FeatureMapsSpecification
  from pytorch_toolbelt.modules.activations import instantiate_activation_block, ACT_GELU
  from pytorch_toolbelt.modules.drop_path import DropPath
label_desc: Use image node_id 7 for calling the MixVisionTransformer obj's underlying member method code with example usage: obj.forward(x) and returns: x