http://hire.jobvite.com/CompanyJobs/Careers.aspx?c=qmQ9Vfw0&su=fxYaVfwk&cs=9AQbVfwg&jvresize=/uk/careers/jobvite-frame-resize.html

import lxml.html as lh
url = 'https://www.fundingcircle.com/uk/careers/'
response = urllib2.urlopen(url)
content = response.read().lower()
root = lh.fromstring(content)
root.xpath("//iframe[contains(@src, 'jobs')]/@src")

http://hire.jobvite.com/companyjobs/careers.aspx?c=qmq9vfw0&su=fxyavfwk&cs=9aqbvfwg&jvresize=/uk/careers/jobvite-frame-resize.html