如何使用selenium与firefox刮网站？

安装Firefox，xvfb，硒

echo "deb http://packages.linuxmint.com debian import" >> /etc/apt/sources.list && apt-get update
apt-get install firefox xvfb python-dev python-pip
pip install pyvirtualdisplay selenium

selenium_scrape.py

from pyvirtualdisplay import Display
import time
from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC
from selenium.common.exceptions import TimeoutException

display = Display(visible=0, size=(800, 600))
display.start()

def init_driver():
    driver = webdriver.Firefox()
    driver.wait = WebDriverWait(driver, 5)
    return driver

def lookup(driver, query):
    driver.get("http://www.google.com")
    try:
    box = driver.wait.until(EC.presence_of_element_located(
        (By.NAME, "q")))
    button = driver.wait.until(EC.element_to_be_clickable(
        (By.NAME, "btnK")))
    box.send_keys(query)
button.click()
    except TimeoutException:
        print("Box or Button not found in google.com")

if __name__ == "__main__":
    driver = init_driver()
    lookup(driver, "Selenium")
    time.sleep(5)
    driver.quit()

display.stop()

错误

  File "selenium_scrape.py", line 20
    box = driver.wait.until(EC.presence_of_element_located(
      ^
IndentationError: expected an indented block