input: def clean_html_tags(text: str) -> str:
      """
      Clean a string of HTML tags.
      
      >>> clean_html_tags("<p>This is a <b>test</b> string</p>")
      'This is a test string'
      
      >>> clean_html_tags("<div><h1>Title</h1><p>Paragraph</p></div>")
      'TitleParagraph'
      """
      import re
      return re.sub(r'<.*?>', '', text)
output:     import re
      return re.sub(r'<.*?>', '', text)