code: def test_types(self):
      self.assertIsInstance(self.processor.correct, bool)
      # self.assertIsInstance(self.processor.st, BarStateSpace)
      # the bar lengths are modelled with individual HMMs
      self.assertIsInstance(self.processor.hmms, list)
      self.assertIsInstance(self.processor.hmms[0], HiddenMarkovModel)
      self.assertIsInstance(
          self.processor.hmms[0].transition_model, BarTransitionModel
      )
      self.assertIsInstance(
          self.processor.hmms[0].observation_model,
          RNNDownBeatTrackingObservationModel,
      )
  
imports: from __future__ import absolute_import, division, print_function
  import unittest
  from os.path import join
  from madmom.ml.hmm import HiddenMarkovModel
  from madmom.audio.chroma import CLPChroma
  from madmom.features import Activations
  from madmom.features.downbeats import *
  from madmom.models import PATTERNS_BALLROOM
  from .None import ACTIVATIONS_PATH, ANNOTATIONS_PATH, AUDIO_PATH, DETECTIONS_PATH
  from .test_utils import DETECTION_FILES
label_desc: Use image node_id 2 for calling the TestDBNDownBeatTrackingProcessorClass obj's underlying member method code with example usage: obj.test_types() without return types