code: def test_correct_parameters_multi_channels(self, boundaries):
      self.assertIsInstance(SignalRandDrop(boundaries), SignalRandDrop)
      sig = convert_to_tensor(np.load(TEST_SIGNAL))
      droped = SignalRandDrop(boundaries)
      dropedsignal = droped(sig)
      self.assertEqual(dropedsignal.shape[1], sig.shape[1])
  
file_path: MONAI/tests/test_signal_rand_drop.py
imports: from __future__ import annotations
  import os
  import unittest
  import numpy
  from parameterized import parameterized
  from monai.transforms import SignalRandDrop
  from monai.utils.type_conversion import convert_to_tensor
label_desc: Use image node_id 1 for calling the TestSignalRandDropTorch obj's underlying member method code with example usage: obj.test_correct_parameters_multi_channels(boundaries) without return types