By.CSS_SELECTOR

# 导包
from selenium import webdriver
from selenium.webdriver.common.by import By
from time import sleep
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC
# 浏览器驱动
driver=webdriver.Chrome()
driver.get(r"D:\XXX\myself\1.html")
sleep(3)
# 寻找元素  点击
# 等找到元素再执行
element=WebDriverWait(driver,10)
.until(EC.visibility_of_element_located((By.CSS_SELECTOR,"#ls_username")))
element.send_keys("fqs")
# driver.find_element(By.NAME,"username").send_keys("fqs")


# 退出
sleep(2)
driver.quit()

解释

 html

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进阶版  基础语法

标签 #id class

# 等找到元素再执行
element=WebDriverWait(driver,10)\
    .until(EC.visibility_of_element_located((By.CSS_SELECTOR,"input#ls_username.pn.vm")))

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1：

属性   严格等于

标签【属性='属性值'】比如  input[id='ls_username']

# 等找到元素再执行
element=WebDriverWait(driver,10)\
    .until(EC.visibility_of_element_located((By.CSS_SELECTOR,"input[id='ls_username']")))

2：

属性  以某某 开头

标签【属性^='属性值的开头部分'】 比如  input[id^='ls_u']

# 等找到元素再执行
element=WebDriverWait(driver,10)\
    .until(EC.visibility_of_element_located((By.CSS_SELECTOR,"input[id^='ls_u']")))

3：

属性  以某某 结尾

标签【属性$='属性值的结尾部分'】比如 input[id$='username']

# 账号<input type="text" name="username" id="ls_username" class="pn vm"><br><br>
element=WebDriverWait(driver,10)\
    .until(EC.visibility_of_element_located((By.CSS_SELECTOR,"input[id$='username']")))

4：

属性  包含 某某

标签【属性*='属性值部分】比如  input[id*='username']

# 账号<input type="text" name="username" id="ls_username" class="pn vm"><br><br>
element=WebDriverWait(driver,10)\
    .until(EC.visibility_of_element_located((By.CSS_SELECTOR,"input[id*='username']")))