Error when executing (TypeError: expected String or buffer)

[charmnQuark]

user@meta:~/mailcrawl$ git clone https://github.com/samwize/python-email-crawler.git  
Cloning into 'python-email-crawler'...
remote: Enumerating objects: 63, done.
remote: Total 63 (delta 0), reused 0 (delta 0), pack-reused 63
Unpacking objects: 100% (63/63), done.
user@meta:~/mailcrawl$ cd python-email-crawler/
user@meta:~/mailcrawl/python-email-crawler$ python email_crawler.py test
[11:51:12] INFO::email_crawler - ----------------------------------------
[11:51:12] INFO::email_crawler - Keywords to Google for: test
[11:51:12] INFO::email_crawler - ----------------------------------------
[11:51:12] INFO::email_crawler - Crawling http://www.google.com/search?q=test&start=0
[11:51:12] ERROR::email_crawler - Exception at url: http://www.google.com/search?q=test&start=0
HTTP Error 503: Service Unavailable
[11:51:12] ERROR::email_crawler - EXCEPTION: expected string or buffer 
Traceback (most recent call last):
  File "email_crawler.py", line 212, in <module>
    crawl(arg)
  File "email_crawler.py", line 65, in crawl
    for url in google_url_regex.findall(data):
TypeError: expected string or buffer
user@meta:~/mailcrawl/python-email-crawler$ 

I get the above when running command.