Q: 153 F: 7 V: 74 L: 2ERROR: cannot concatenate 'str' and 'NoneType' objects
Traceback (most recent call last):
  File "/usr/lib/python2.7/site-packages/spyda/crawler.py", line 114, in crawl
    links = list(get_links(content))
  File "/usr/lib/python2.7/site-packages/spyda/utils.py", line 150, in get_links
    tags = parse_html(html).cssselect("a")
  File "/usr/lib/python2.7/site-packages/spyda/utils.py", line 142, in parse_html
    return html_to_doc(html)
  File "/usr/lib/python2.7/site-packages/lxml/html/soupparser.py", line 23, in fromstring
    return _parse(data, beautifulsoup, makeelement, **bsargs)
  File "/usr/lib/python2.7/site-packages/lxml/html/soupparser.py", line 66, in _parse
    tree = beautifulsoup(source, **bsargs)
  File "/usr/lib/python2.7/site-packages/BeautifulSoup.py", line 1522, in __init__
    BeautifulStoneSoup.__init__(self, *args, **kwargs)
  File "/usr/lib/python2.7/site-packages/BeautifulSoup.py", line 1147, in __init__
    self._feed(isHTML=isHTML)
  File "/usr/lib/python2.7/site-packages/BeautifulSoup.py", line 1189, in _feed
    SGMLParser.feed(self, markup)
  File "/usr/lib/python2.7/sgmllib.py", line 103, in feed
    self.rawdata = self.rawdata + data
TypeError: cannot concatenate 'str' and 'NoneType' objects