#-*- coding: utf-8 -*-# Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserved## Licensed under the Apache License, Version 2.0 (the "License");# you may not use this file except in compliance with the License.# You may obtain a copy of the License at## http://www.apache.org/licenses/LICENSE-2.0## Unless required by applicable law or agreed to in writing, software# distributed under the License is distributed on an "AS IS" BASIS,# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.# See the License for the specific language governing permissions and# limitations under the License."""dataset"""classDataset(object):"""An abstract class represening Dataset. Generally, all datasets should subclass it. All subclasses should overwrite :code:`__getitem__` and :code:`__len__`. """def__len__(self):raiseNotImplementedErrordef__getitem__(self,idx):raiseNotImplementedErrorclassStreamDataset(object):"""An abstract class represening StreamDataset which has unknown length. Generally, all unknown length datasets should subclass it. All subclasses should overwrite :code:`__iter__`. """def__iter__(self):raiseNotImplementedError