code: def _get_driver(driver_type):
      
      if driver_type == 'phantomjs':
          return webdriver.PhantomJS(service_log_path=os.path.devnull)
      if driver_type == 'firefox':
          return webdriver.Firefox(firefox_options=FIREFOXOPTIONS)
      elif driver_type == 'chrome':
          chrome_options = webdriver.ChromeOptions()
          for arg in CHROME_WEBDRIVER_ARGS:
              chrome_options.add_argument(arg)
          return webdriver.Chrome(chrome_options=chrome_options)
      else:
          raise USPSError('{} not supported'.format(driver_type))
docs: Get webdriver.