text: """
  Licensed to the Apache Software Foundation (ASF) under one
  or more contributor license agreements.  See the NOTICE file
  distributed with this work for additional information
  regarding copyright ownership.  The ASF licenses this file
  to you 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.
  """
  import uuid
  from concurrent.futures import Future
  from six.moves import queue
  
  from gremlin_python.driver import resultset
  
  __author__ = 'David M. Brown (davebshow@gmail.com)'
  
  
  class Connection:
  
      def __init__(self, url, traversal_source, protocol, transport_factory,
                   executor, pool, headers=None):
          self._url = url
          self._headers = headers
          self._traversal_source = traversal_source
          self._protocol = protocol
          self._transport_factory = transport_factory
          self._executor = executor
          self._transport = None
          self._pool = pool
          self._results = {}
          self._inited = False
  
      def connect(self):
          if self._transport:
              self._transport.close()
          self._transport = self._transport_factory()
          self._transport.connect(self._url, self._headers)
          self._protocol.connection_made(self._transport)
          self._inited = True
  
      def close(self):
          if self._inited:
              self._transport.close()
  
      def write(self, request_message):
          if not self._inited:
              self.connect()
          request_id = str(uuid.uuid4())
          result_set = resultset.ResultSet(queue.Queue(), request_id)
          self._results[request_id] = result_set
          # Create write task
          future = Future()
          future_write = self._executor.submit(
              self._protocol.write, request_id, request_message)
  
          def cb(f):
              try:
                  f.result()
              except Exception as e:
                  future.set_exception(e)
                  self._pool.put_nowait(self)
              else:
                  # Start receive task
                  done = self._executor.submit(self._receive)
                  result_set.done = done
                  future.set_result(result_set)
  
          future_write.add_done_callback(cb)
          return future
  
      def _receive(self):
          try:
              while True:
                  data = self._transport.read()
                  status_code = self._protocol.data_received(data, self._results)
                  if status_code != 206:
                      break
          finally:
              self._pool.put_nowait(self)
  