License

Copyright 2019 Google, Inc.Licensed to the Apache Software Foundation (ASF) under one or more contributorlicense agreements. See the NOTICE file distributed with this work foradditional information regarding copyright ownership. The ASF licenses thisfile to you under the Apache License, Version 2.0 (the "License"); you may notuse this file except in compliance with the License. You may obtain a copy ofthe License athttp://www.apache.org/licenses/LICENSE-2.0Unless required by applicable law or agreed to in writing, softwaredistributed under the License is distributed on an "AS IS" BASIS, WITHOUTWARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See theLicense for the specific language governing permissions and limitations underthe License.