from selenium import webdriver

from selenium.webdriver.chrome.options import Options

mobile_emulation = {

   "deviceMetrics": { "width": 360, "height": 640, "pixelRatio": 3.0 },

   "userAgent": "Mozilla/5.0 (Linux; Android 4.2.1; en-us; Nexus 5 Build/JOP40D) AppleWebKit/535.19 (KHTML, like Gecko) Chrome/18.0.1025.166 Mobile Safari/535.19" }

chrome_options = Options()
chrome_options.add_argument("--headless")
chrome_options.add_argument("--disable-gpu")

chrome_options.add_experimental_option("mobileEmulation", mobile_emulation)

driver = webdriver.Chrome(chrome_options = chrome_options)

driver.get('https://nhentai.net')
driver.save_screenshot("screenshot.png")
driver.quit()