text: # Copyright 2018 Google LLC
  #
  # 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
  #
  #     https://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.
  
  import os
  import time
  
  from google.cloud import trace_v2
  from google.cloud.trace_v2.proto import trace_pb2
  from google.cloud.trace_v2.proto import tracing_pb2
  
  
  class TestSystemTraceService(object):
      def test_batch_write_spans(self):
          project_id = os.environ['PROJECT_ID']
  
          client = trace_v2.TraceServiceClient()
          name = client.project_path(project_id)
          spans = []
          client.batch_write_spans(name, spans)
  