'Get a local object for a locally unique ID.
@return: An object previously stored with L{registerReference} or
L{None} if there is no object which corresponds to the given
identifier.'

def localObjectForID(self, luid):

    if isinstance(luid, unicode):
        luid = luid.encode('utf8')
    lob = self.localObjects.get(luid)
    if (lob is None):
        return
    return lob.object
