code: def test_WarmupStepLR():
      linear = torch.nn.Linear(2, 2)
      opt = torch.optim.SGD(linear.parameters(), 0.1)
      sch = WarmupStepLR(opt)
      lr = opt.param_groups[0]["lr"]
  
      opt.step()
      sch.step()
      lr2 = opt.param_groups[0]["lr"]
      assert lr != lr2
  
      sch.step_num = sch.warmup_steps + 1
      opt.step()
      sch.step()
      lr3 = opt.param_groups[0]["lr"]
      assert lr2 != lr3
  
label_desc: Use image node_id 1 for calling a global function with example usage: test_WarmupStepLR() without return types