'Removes passed multi-tracker from this torrent'

def remove_multitracker(self, tracker):

    for tl in self.content.get(u'announce-list', [])[:]:
        try:
            tl.remove(tracker)
            self.modified = True
            if (not tl):
                self.content[u'announce-list'].remove(tl)
        except (AttributeError, ValueError):
            pass
