Scraping a javascript RSSI indicator

[jon333]

I have a Raspberry Pi connected to a Verizon MiFi LTE modem/router. I am trying to scrape the RSSI signal from the 'welcome page' of the device. No login is required and I'm able to get the 200 status code and also view the page content. I'm not really sure where to go from there. I'm not sure any lxml class would recognize it. Any ideas?

from lxml import html
import requests

page = requests.get('<removed>',  headers={'User-Agent':'test'})

tree = html.fromstring(page.content)

rssi = tree.xpath('//*[@id="statusBar_rssi"]')

print (rssi)

returns []

Here is what Chrome inspector shows -

<li id="item_statusBar_rssi"><span id="statusBar_rssi" style=""><div class="rssi_4"></div>Data</span></li>

The div changes with the number of bars displayed.

Thank you.