code: def __init__(self, optimizer, curr_iter, max_iter, lr_decay):
      self.max_iter = float(max_iter)
      self.init_lr_groups = []
      for p in optimizer.param_groups:
          self.init_lr_groups.append(p["lr"])
      self.param_groups = optimizer.param_groups
      self.curr_iter = curr_iter
      self.lr_decay = lr_decay
  
imports: import os
  from math import ceil
  import numpy
  import torch
  import torch.nn.functional
  from torch import nn
label_desc: Use image node_id 1 to create a new PolyLR object  with example: obj = PolyLR(optimizer, curr_iter, max_iter, lr_decay)