Scrapy 中的 Lua 脚本

我正在使用 scrapy 1.6 和 splash 3.2。我有以下代码：

import scrapy
import random
from scrapy_splash import SplashRequest
from scrapy.utils.response import open_in_browser
from scrapy.linkextractors import LinkExtractor

USER_AGENT = 'Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:48.0) Gecko/20100101 Firefox/48.0'

class MySpider(scrapy.Spider):

    start_urls = ["http://yahoo.com"]
    name = 'mytest'

    def start_requests(self):
        for url in self.start_urls:
            yield SplashRequest(url, self.parse, endpoint='render.html', args={'wait': 2.5},headers={'User-Agent': USER_AGENT,'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8'})

    def parse(self, response):
        # response.body is a result of render.html call; it
        # contains HTML processed by a browser.
        # from scrapy.http.response.html import HtmlResponse
        # ht = HtmlResponse('jj')
        # ht.body.replace =response
        open_in_browser(response)
        return None

我正在阅读 https://blog.scrapinghub.com/2015/03/02/handling-javascript-in-scrapy-with-splash ，他们在其中给出了一个例子：

function main(splash)
assert(splash:go(splash.args.url))
splash:wait(0.5)
local title = splash:evaljs("document.title")
return {title=title}
end

显然，我不能把 Lua 放在我的 python 脚本中。我该把它放在哪里，如何访问它并将其传递给我的 splash 请求？