class_docstr: Given a block of HTML, group the content under the preceding
  heading tags which can then be used for creating an index
  for that section.
docstr: Called for the text contents of each tag.
docstr_tok: ["Called","for","the","text","contents","of","each","tag","."]
code: def handle_data(self, data: str) -> None:
      """Called for the text contents of each tag."""
      self._stripped_html.append(data)
  
      if self.section is None:
          # This means we have some content at the start of the
          # HTML before we reach a heading tag. We don't actually
          # care about that content as it will be added to the
          # overall page entry in the search. So just skip it.
          return
  
      # If this is a header, then the data is the title.
      # Otherwise it is content of something under that header
      # section.
      if self.is_header_tag:
          self.section.title = data
      else:
          self.section.text.append(data.rstrip("\n"))
  
imports: from __future__ import annotations
  import json
  import logging
  import os
  import re
  import subprocess
  from html.parser import HTMLParser
  from typing import TYPE_CHECKING
label_desc: Use image node_id 4 for calling the ContentParser obj's underlying member method code with example usage: obj.handle_data(data) without return types