I am trying to get src(URL) link of main image from xkcd.com website. I am using the following code but it returns something like `session="2f69dd2e-b377-4d1f-9779-16dad1965b81", element="{ca4e825a-88d4-48d3-a564-783f9f976c6b}"`

```
from selenium import webdriver
from selenium.webdriver.common.keys import Keys

browser = webdriver.Firefox()

browser.get('http://xkcd.com')
assert 'xkcd' in browser.title

idlink= browser.find_element_by_id("comic")

#link = idlink.get_attribute("src") ## print link prints null

print idlink

```

using xpath method also returns same as above.