Tracebook thrown in scrapy unittest

gistfile1.py

Traceback (most recent call last):
  File "/Users/ciferkey/Projects/scraper/scraper/spiders/scraper_spider.py", line 26, in test_parse_bank_page
    print ScraperSpider.parse_bank_page(self.s, r)
  File "/Users/ciferkey/Projects/scraper/scraper/spiders/scraper_spider.py", line 127, in parse_bank_page
    institution_id = hxs.select(x_id).extract()[0]
  File "/Users/ciferkey/.virtualenvs/scraper/lib/python2.7/site-packages/scrapy/selector/lxmlsel.py", line 51, in select
    result = self.xpathev(xpath)
  File "/Users/ciferkey/.virtualenvs/scraper/lib/python2.7/site-packages/scrapy/selector/lxmlsel.py", line 46, in xpathev
    self._xpathev = etree.XPathEvaluator(self.root, namespaces=self.namespaces)
  File "/Users/ciferkey/.virtualenvs/scraper/lib/python2.7/site-packages/scrapy/selector/lxmlsel.py", line 40, in root
    base_url=self.response.url)
  File "lxml.etree.pyx", line 2743, in lxml.etree.fromstring (src/lxml/lxml.etree.c:52665)
  File "parser.pxi", line 1573, in lxml.etree._parseMemoryDocument (src/lxml/lxml.etree.c:79932)
  File "parser.pxi", line 1452, in lxml.etree._parseDoc (src/lxml/lxml.etree.c:78774)
  File "parser.pxi", line 960, in lxml.etree._BaseParser._parseDoc (src/lxml/lxml.etree.c:75389)
  File "parser.pxi", line 564, in lxml.etree._ParserContext._handleParseResultDoc (src/lxml/lxml.etree.c:71739)
  File "parser.pxi", line 645, in lxml.etree._handleParseResult (src/lxml/lxml.etree.c:72614)
  File "parser.pxi", line 596, in lxml.etree._raiseParseError (src/lxml/lxml.etree.c:72123)
XMLSyntaxError: None