class_docstr: Test FeatureVisualizer base class
class_docstr_tok: ["Test","FeatureVisualizer","base","class"]
docstr: Check the visualizer/transformer class hierarchy
code: def test_subclass(self):
      """
      Check the visualizer/transformer class hierarchy
      """
      visualizer = FeatureVisualizer()
      assert isinstance(visualizer, TransformerMixin)
      assert isinstance(visualizer, BaseEstimator)
      assert isinstance(visualizer, Visualizer)
  
imports: import pytest
  import numpy
  import numpy.testing
  from tests.fixtures import Dataset
  from yellowbrick.base import Visualizer
  from yellowbrick.features.base import *
  from sklearn.base import BaseEstimator, TransformerMixin
  from sklearn.datasets import make_classification, make_regression
  from unittest.mock import Mock
label_desc: Use image node_id 1 for calling the TestFeatureVisualizer obj's underlying member method code with example usage: obj.test_subclass() without return types