Pss.... Оказалось очень просто:
webdriver.DesiredCapabilities.PHANTOMJS['proxy']={"httpProxy":'94.20.21.38:3128', "proxyType":"MANUAL"}from selenium import webdriver
from selenium.webdriver.common.desired_capabilities import DesiredCapabilities
webdriver.DesiredCapabilities.PHANTOMJS['proxy']={"httpProxy":'94.20.21.38:3128', "proxyType":"MANUAL"}
driver = webdriver.Remote(command_executor='http://127.0.0.1:4444/wd/hub', desired_capabilities=DesiredCapabilities.PHANTOMJS)
driver.get('https://www.iplocation.net/')
x=driver.find_element_by_xpath('//p[contains(text(),"Your public IP Address is")]')
if x is not None: print x.text
Вопрос снят. Всем спасибо!