class_docstr: PosTag (Part of Speech Tagging Visualizer) Tests
docstr: Assert no errors occur during PosTagVisualizer integration
  with raw corpus to be parsed using spacy
docstr_tok: ["Assert","no","errors","occur","during","PosTagVisualizer","integration","with","raw","corpus","to","be","parsed","using","spacy"]
code: def test_spacy_raw(self):
      """
      Assert no errors occur during PosTagVisualizer integration
      with raw corpus to be parsed using spacy
      """
      visualizer = PosTagVisualizer(parser="spacy", tagset="universal")
      visualizer.fit(sonnets)
      visualizer.ax.grid(False)
  
      self.assert_images_similar(visualizer)
  
imports: import pytest
  import matplotlib.pyplot
  from tests.base import VisualTestCase
  from tests.base import IS_WINDOWS_OR_CONDA
  from yellowbrick.text.postag import *
  from yellowbrick.exceptions import YellowbrickValueError
label_desc: Use image node_id 7 for calling the TestPosTag obj's underlying member method code with example usage: obj.test_spacy_raw() without return types