Using a python script in google chrome extension

I have written a python script using NLTK to get sentiment of text. I am trying to build a Google Chrome extension that gets the selected text and displays the sentiment of the text.

I did see Native Messaging but it doesn't seem to work, they have used an app as the sample.

Is there a way where I can get the selected text from the extension and then send it to my python script and then make the extension display the sentiment of the text?

I did watch ajax tutorials too but to no avail.