Auto Message to FB Group by Selenium Bot

sel_bot_fb_grp_msg.py

from time import sleep
from selenium import webdriver
from selenium.webdriver.common.keys import Keys
from selenium.webdriver.common.by import By
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC
 
def main():
 
    # Your Facebook account user and password
    usr = str(input("Enter User Email ID:"))
    pwd = str(input("Enter User Password:"))
    message = "Auto FB Group Message through Selenium Bot."
    #set multiple fb groups here
    group_links =              [
        "https://web.facebook.com/groups/python.eshikhon","https://web.facebook.com/messages/t/2613328745398719"
    ] 
 
     
    chrome_options = webdriver.ChromeOptions()
    chrome_options.add_experimental_option("detach", True)
    chrome_options.add_argument("--disable-infobars")
    chrome_options.add_experimental_option("prefs", { \
        "profile.default_content_setting_values.notifications": 2 # 1:allow, 2:block 
    })
 
    driver = webdriver.Chrome(executable_path="driver/chromedriver")
    driver.implicitly_wait(5) # seconds
 
    # Go to facebook.com
    driver.get("http://www.facebook.com")
     
    # Enter user email
    elem = driver.find_element_by_id("email")
    elem.send_keys(usr)
    # Enter user password
    elem = driver.find_element_by_id("pass")
    elem.send_keys(pwd)
    # Login
    elem.send_keys(Keys.RETURN)
 
    for group in group_links:
 
        # Go to the Facebook Group
        driver.get(group)
 
        # Click the post box
        post_box=driver.find_element_by_xpath("//*[@name='xhpc_message_text']")
 
        # Enter the text we want to post to Facebook
        post_box.send_keys(message)
        
        sleep(5)
        buttons = driver.find_elements_by_tag_name("button")
        sleep(5)
        for button in buttons:
            if button.text == "Post":
                button.click()
                sleep(10)
                print("post done")
 
    driver.close()
    
 
if __name__ == '__main__':
  main()

post_box=driver.find_element_by_xpath("//*[@name='xhpc_message_text']") me sale error alguna solucion ?