Access an html file from a python file

I have a dropdown in a html page, i have created a redirect from that page to a .py file in Django. the .py code consists of a field

cursor.execute ("select seller_ID, Website from Details where Marketplace='Snapdeal'")

now in place of 'Snapdeal', i want to have a variable pointing to the selection of my dropdown in the html page from where this is redirected to. How can I do it?