优化CSSElement 定位

[defnngj]

from poium import Page, CSSElement
from time import sleep
from selenium import webdriver

class baiduPage(Page):
    a = CSSElement("#s-top-left > a adfasd")

dr = webdriver.Chrome()
page = baiduPage(dr)
page.get("https://www.baidu.com")

page.a.click()

错误信息：

selenium.common.exceptions.JavascriptException: Message: javascript error: Cannot read property 'style' of undefined

错误是元素定位，优化poium ，增加元素判断。