+ try:
+ content = webpage_bytes.decode(encoding, 'replace')
+ except LookupError:
+ content = webpage_bytes.decode('utf-8', 'replace')
+
+ if (u'<title>Access to this site is blocked</title>' in content and
+ u'Websense' in content[:512]):
+ msg = u'Access to this webpage has been blocked by Websense filtering software in your network.'
+ blocked_iframe = self._html_search_regex(
+ r'<iframe src="([^"]+)"', content,
+ u'Websense information URL', default=None)
+ if blocked_iframe:
+ msg += u' Visit %s for more details' % blocked_iframe
+ raise ExtractorError(msg, expected=True)
+