code: def test_lambda_scheduler(self):
      def noise_lambda(epoch):
          return 1 - epoch / 10
  
      scheduler = LambdaNoise(self.optimizer, noise_lambda=noise_lambda)
  
      self.assertEqual(self.optimizer.noise_multiplier, 1.0)
      scheduler.step()
      self.assertEqual(self.optimizer.noise_multiplier, noise_lambda(1))
  
file_path: opacus/opacus/tests/schedulers/noise_scheduler_test.py
imports: import unittest
  import torch
  from opacus import PrivacyEngine
  from opacus.schedulers import ExponentialNoise, LambdaNoise, StepNoise
  from torch import nn, optim
  from torch.utils.data import DataLoader, TensorDataset
label_desc: Use image node_id 4 for calling the NoiseSchedulerTest obj's underlying member method code with example usage: obj.test_lambda_scheduler() and returns: unknown