def provStacks(self, offs, size):
        '''
        Returns a stream of provenance stacks at the given offset
        '''
        for _, iden in self.provseq.slice(offs, size):
            stack = self.getProvStack(iden)
            if stack is None:
                continue
            yield (iden, stack)
def provStacks ( self , offs , size ) : for _ , iden in self . provseq . slice ( offs , size ) : stack = self . getProvStack ( iden ) if stack is None : continue yield ( iden , stack )
Returns a stream of provenance stacks at the given offset