lyrics: fix crash when beautifulsoup4 is not installed
Fixes
@@ -760,7 +760,7 @@ class LyricsPlugin(plugins.BeetsPlugin):
def sanitize_bs_sources(self, sources):
enabled_sources = []
for source in sources:
- if source.REQUIRES_BS:
+ if self.SOURCE_BACKENDS[source].REQUIRES_BS:
self._log.debug(u'To use the %s lyrics source, you must '
u'install the beautifulsoup4 module. See '
u'the documentation for further details.'
