code: def _getbug(self, objid, **kwargs):
          
          return self._getbugs([objid], permissive=False, **kwargs)[0]
docs: Thin wrapper around _getbugs to handle the slight argument tweaks
          for fetching a single bug. The main bit is permissive=False, which
          will tell bugzilla to raise an explicit error if we can't fetch
          that bug.
  
          This logic is called from Bug() too