找到问题的那一刻，骂了自己N次的猪脑子！！！
问题：爬虫脚本本来一切正常的，临时有其他事情耽搁了，然后回头正式运行的时候发现一只报错 [twisted] CRITICAL: Unhandled error in Deferred，错误就是下面这样的（因为都一样的错误，所以直接从网上贴过来的）：
2016-03-13 08:50:50 [scrapy] INFO: Enabled extensions: CloseSpider, TelnetConsole, LogStats, CoreStats, SpiderState
Unhandled error in Deferred:
2016-03-13 08:50:50 [twisted] CRITICAL: Unhandled error in Deferred:
Traceback (most recent call last):
File "/usr/local/lib/python2.7/dist-packages/scrapy/cmdline.py", line 150, in _run_command
cmd.run(args, opts)
File "/usr/local/lib/python2.7/dist-packages/scrapy/commands/crawl.py", line 57, in run
self.crawler_process.crawl(spname, **opts.spargs)
File "/usr/local/lib/python2.7/dist-packages/scrapy/crawler.py", line 153, in crawl
d = crawler.crawl(*args, **kwargs)
File "/usr/local/lib/python2.7/dist-packages/twisted/internet/defer.py", line 1274, in unwindGenerator
return _inlineCallbacks(None, gen, Deferred())
--- <exception caught here> ---
File "/usr/local/lib/python2.7/dist-packages/twisted/internet/defer.py", line 1128, in _inlineCallbacks
result = g.send(result)
File "/usr/local/lib/python2.7/dist-packages/scrapy/crawler.py", line 70, in crawl
self.spider = self._create_spider(*args, **kwargs)
File "/usr/local/lib/python2.7/dist-packages/scrapy/crawler.py", line 80, in _create_spider
return self.spidercls.from_crawler(self, *args, **kwargs)
File "/usr/local/lib/python2.7/dist-packages/scrapy/spiders/crawl.py", line 91, in from_crawler
spider = super(CrawlSpider, cls).from_crawler(crawler, *args, **kwargs)
File "/usr/local/lib/python2.7/dist-packages/scrapy/spiders/__init__.py", line 50, in from_crawler
spider = cls(*args, **kwargs)
exceptions.TypeError: __init__() takes at least 3 arguments (1 given)
2016-03-13 08:50:50 [twisted] CRITICAL:问题解决思路：
1、网上有说可能是twisted版本过高的，本人scrapy版本为1.3.3，twisted版本为13.1.0，已经是1.3.3版本要求的最低的twisted版本，依然不行。
2、有考虑过pip源的问题，所以换了源，依然不行。（但是本人之前在安装cryptography库的时候确实是因为pypi源有问题，更换为非官方的库就好了。）
官方库下载地址：https://pypi.org/
非官方库下载地址：https://www.lfd.uci.edu/~gohlke/pythonlibs/#numpy
3、在python安装目录script下运行安装：
python C:\Python36\Scripts\pywin32_postinstall.py -install
依然不行！！！
问题解决：
要崩溃了，然后看到 Stack Overflow上一个人（https://stackoverflow.com/questions/35970518/scrapy-twisted-critical-unhandled-error-in-deferred）解决这个问题的思路，灵光一闪，对比一下自己代码及配置文件，然后就发现上次清理文件时手残的把scrapy.cfg配置文件删除了！！！
所以出现诡异报错时还是要认真检查配置项呀。