title: python universal feedparser crashing on unicode error
body: <p>I am using OSX 10.6 and python 2.7.1 with BeautifulSoup 3.0 and feedparser 5.01.
   I am trying to parse the New York Times RSS Feed, which validates, and which Beautiful Soup on its own will parse happily.</p>
  
  <p>The minimum code to produce the error is:</p>
  
  <pre><code>import feedparser
  from BeautifulSoup import BeautifulSoup
  
  
  feed = feedparser.parse("http://www.nytimes.com/services/xml/rss/nyt/GlobalHome.xml")
  </code></pre>
  
  <ul>
  <li>It fails if I use either the url or
  if I use urllib2.urlopen to get the
  contents. </li>
  <li>I have also tried the character set detector.</li>
  </ul>
  
  <p>The error block is:</p>
  
  <pre><code> /Users/user/Source/python/feed/BeautifulSoup.py:1553: UnicodeWarning: Unicode equal comparison failed to convert both arguments to Unicode - interpreting them as being unequal
    elif data[:3] == '\xef\xbb\xbf':
  /Users/user/Source/python/feed/BeautifulSoup.py:1556: UnicodeWarning: Unicode equal comparison failed to convert both arguments to Unicode - interpreting them as being unequal
    elif data[:4] == '\x00\x00\xfe\xff':
  /Users/user/Source/python/feed/BeautifulSoup.py:1559: UnicodeWarning: Unicode equal comparison failed to convert both arguments to Unicode - interpreting them as being unequal
    elif data[:4] == '\xff\xfe\x00\x00':
  Traceback (most recent call last):
    File "parse.py", line 5, in &lt;module&gt;
      feed = feedparser.parse("http://www.nytimes.com/services/xml/rss/nyt/GlobalHome.xml")
    File "/Users/user/Source/python/feed/feedparser.py", line 3822, in parse
      feedparser.feed(data.decode('utf-8', 'replace'))
    File "/Users/user/Source/python/feed/feedparser.py", line 1851, in feed
      sgmllib.SGMLParser.feed(self, data)
    File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/sgmllib.py", line 104, in feed
      self.goahead(0)
    File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/sgmllib.py", line 143, in goahead
      k = self.parse_endtag(i)
    File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/sgmllib.py", line 320, in parse_endtag
      self.finish_endtag(tag)
    File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/sgmllib.py", line 360, in finish_endtag
      self.unknown_endtag(tag)
    File "/Users/user/Source/python/feed/feedparser.py", line 657, in unknown_endtag
      method()
    File "/Users/user/Source/python/feed/feedparser.py", line 1545, in _end_description
      value = self.popContent('description')
    File "/Users/user/Source/python/feed/feedparser.py", line 961, in popContent
      value = self.pop(tag)
    File "/Users/user/Source/python/feed/feedparser.py", line 868, in pop
      mfresults = _parseMicroformats(output, self.baseuri, self.encoding)
    File "/Users/user/Source/python/feed/feedparser.py", line 2420, in _parseMicroformats
      p = _MicroformatsParser(htmlSource, baseURI, encoding)
    File "/Users/user/Source/python/feed/feedparser.py", line 2024, in __init__
      self.document = BeautifulSoup.BeautifulSoup(data)
    File "/Users/user/Source/python/feed/BeautifulSoup.py", line 1228, in __init__
      BeautifulStoneSoup.__init__(self, *args, **kwargs)
    File "/Users/user/Source/python/feed/BeautifulSoup.py", line 892, in __init__
      self._feed()
    File "/Users/user/Source/python/feed/BeautifulSoup.py", line 917, in _feed
      SGMLParser.feed(self, markup)
    File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/sgmllib.py", line 103, in feed
      self.rawdata = self.rawdata + data
  TypeError: cannot concatenate 'str' and 'NoneType' objects
  </code></pre>
  
  <p>I would appreciate any advice very much.</p>