reading html and edit chekcbox to html

[jacklee26]

I have a question about reading HTML files, and edit by adding a checkbox before a tag on every link.

I have a test.html that looks like this:

<a href="https://www.google.com">Link </a><br><a href="https://www.youtube.com">Link </a><br><a href="https://www.instagram.com">Link </a><br>

i wish my output will be like this, add a checkbox before each link which should look like this

<input type="checkbox"> <a href="https://www.google.com">Link </a><br>
<input type="checkbox"> <a href="https://www.youtube.com">Link </a>
<input type="checkbox"> <a href="https://www.instagram.com">Link </a>

Do anyone have any idea i try like this but seem not working

lines = []
#open file
with open(r'test.html', mode='r') as f:
    for line in f.readlines(): # iterate thru the lines    
        if '<br>' in line:
            text = '<input type="checkbox">'
            lines.append(text)    
            lines.append(line)
        

#write to a new file
with open(test.html', mode='w') as new_f:
    new_f.writelines(lines)

I think I need to add a new line after <br> else it won't work.
Does anyone know how to do solve it?

Step:
Read test.html
edit the test.html adding <checkkbox> before a tag