code: def grab_selenium_driver(driver_name=None):
      
      from selenium import webdriver
      if driver_name is None:
          driver_name = 'firefox'
      if driver_name.lower() == 'chrome':
          grab_selenium_chromedriver()
          return webdriver.Chrome()
      elif driver_name.lower() == 'firefox':
          # grab_selenium_chromedriver()
          return webdriver.Firefox()
      else:
          raise AssertionError('unknown name = %r' % (driver_name,))
docs: pip install selenium -U