code: def test_PiecewiseScheduler_with_one_value(self):
      scheduler = PiecewiseScheduler([(0, 0.1)])
      for i in range(10):
          value = scheduler.step()
          assert value == 0.1
  
      scheduler = PiecewiseScheduler([(3, 0.1)])
      for i in range(10):
          value = scheduler.step()
          assert value == 0.1
  
file_path: PARL/parl/utils/tests/scheduler_test.py
imports: import unittest
  import numpy
  from parl.utils.scheduler import *
label_desc: Use image node_id 2 for calling the TestScheduler obj's underlying member method code with example usage: obj.test_PiecewiseScheduler_with_one_value() without return types