Selenium.WebDriver is trying to access the HTML source of the Web element

I'm using Python binding to spin the Selenium web driver.

from selenium import webdriver
wd = webdriver.Firefox()

Here

I know this much, but I still don't know how to view the element source.

lem.source # <-- return HTML in string format

I'm looking for a Python selenium webdriver document, but I don't know if I can't find it or not, but I don't know anyway.

Help me.