code: def test_linear_schedule():
      """
      test LinearSchedule
      """
      linear_sched = LinearSchedule(
          schedule_timesteps=100, initial_p=0.2, final_p=0.8
      )
      assert np.isclose(linear_sched.value(50), 0.5)
      assert np.isclose(linear_sched.value(0), 0.2)
      assert np.isclose(linear_sched.value(100), 0.8)
  
      linear_sched = LinearSchedule(
          schedule_timesteps=100, initial_p=0.8, final_p=0.2
      )
      assert np.isclose(linear_sched.value(50), 0.5)
      assert np.isclose(linear_sched.value(0), 0.8)
      assert np.isclose(linear_sched.value(100), 0.2)
  
      linear_sched = LinearSchedule(
          schedule_timesteps=100, initial_p=-0.6, final_p=0.2
      )
      assert np.isclose(linear_sched.value(50), -0.2)
      assert np.isclose(linear_sched.value(0), -0.6)
      assert np.isclose(linear_sched.value(100), 0.2)
  
      linear_sched = LinearSchedule(
          schedule_timesteps=100, initial_p=0.2, final_p=-0.6
      )
      assert np.isclose(linear_sched.value(50), -0.2)
      assert np.isclose(linear_sched.value(0), 0.2)
      assert np.isclose(linear_sched.value(100), -0.6)
  
imports: import numpy
  from stable_baselines.common.schedules import ConstantSchedule, PiecewiseSchedule, LinearSchedule
label_desc: Use image node_id 3 for calling a global function with example usage: test_linear_schedule() without return types