Python pypdf code to add bookmarks

I have the following code to recast a set of medical records so that the new PDF has bookmarks that reflect the date of medical treatment. The code creates a new PDF but the pdf has no bookmarks. Thank you in advance for any help.

import re
import pypdf

Open the PDF file for reading

pdf_file = open(“C:/Users/stand/Downloads/SusanJonesVisitDate.pdf”, ‘rb’)
pdf_reader = pypdf.PdfReader(pdf_file)
pdf_writer = pypdf.PdfWriter()

Define the regular expression for finding the bookmark locations

regex = re.compile(r’Visit date: \b\d{2}/\d{2}/\d{4}\b’)

Iterate through the pages of the PDF

for i in range(len(pdf_reader.pages)):
page = pdf_reader.pages[i]
text = page.extract_text()
matches = re.finditer(regex, text)

for match in matches:
pdf_writer.add_outline_item( title=matches, page_number=page)

Write the new PDF file with bookmarks

output_file = open(‘porejemplo.pdf’, ‘wb’)