class_docstr: Universal Transformer(https://arxiv.org/pdf/1807.03819.pdf) with ACT(https://arxiv.org/pdf/1603.08983.pdf).
code: def reset_stat(self):
      self.stat = [0] * (self.MAX_DEPTH + 1)
  
imports: from .attention import *
  from .layers import *
  from .functions import *
  from .embedding import *
  import dgl.function
  import torch
  import torch.nn.init
label_desc: Use image node_id 2 for calling the UTransformer obj's underlying member method code with example usage: obj.reset_stat() without return types