Find Element by xpath in python using selenium Webdriver -

how can find these xpath.

<a class="single_like_button btn3-wrap" onclick="openfblwin_2224175();"> <span>&nbsp;</span><div class="btn3">like</div></a> 

and

<button value="1" class="_42ft _4jy0 pagelikebutton _4jy4 _517h _9c6" data-profileid="776072132447222" data-ownerid="u_jsonp_2_t" id="u_jsonp_2_u" type="submit"><i class="_3-8_ img sp_wmp_mjdzgeq sx_96dbd2"></i>like</button> 

supposed elements have class names being unique in tree, can use find_element_by_xpath.

for a:

find_element_by_xpath('.//a[@class="single_like_button btn3-wrap"]') 

and button:

find_element_by_xpath('.//button[@class="_42ft _4jy0 pagelikebutton _4jy4 _517h _9c6"]') 

of course can use tree path element, cannot answered due incomplete source.

hope helps.