new_contents: import logging
  import multiprocessing
  import os
  import threading
  import unittest
  
  from integration_tests.env_variable_names import SLACK_SDK_TEST_USER_TOKEN
  from integration_tests.helpers import async_test
  from slack import WebClient
  
  
  class TestWebClient(unittest.TestCase):
      """Runs integration tests with real Slack API
      https://github.com/slackapi/python-slackclient/issues/480
      """
  
      def setUp(self):
          self.logger = logging.getLogger(__name__)
          self.user_token = os.environ[SLACK_SDK_TEST_USER_TOKEN]
          self.sync_client: WebClient = WebClient(token=self.user_token, run_async=False)
          self.async_client: WebClient = WebClient(token=self.user_token, run_async=True)
  
      def tearDown(self):
          pass
  
      def test_issue_480_processes(self):
          client = self.sync_client
          before = len(multiprocessing.active_children())
          for idx in range(10):
              response = client.api_test()
              self.assertIsNotNone(response)
          after = len(multiprocessing.active_children())
          self.assertEqual(0, after - before)
  
      @async_test
      async def test_issue_480_processes_async(self):
          client = self.async_client
          before = len(multiprocessing.active_children())
          for idx in range(10):
              response = await client.api_test()
              self.assertIsNotNone(response)
          after = len(multiprocessing.active_children())
          self.assertEqual(0, after - before)
  
      # fails with Python 3.6
      def test_issue_480_threads(self):
          client = self.sync_client
          before = threading.active_count()
          for idx in range(10):
              response = client.api_test()
              self.assertIsNotNone(response)
          after = threading.active_count()
          self.assertEqual(0, after - before)
  
      # fails with Python 3.6
      @async_test
      async def test_issue_480_threads_async(self):
          client = self.async_client
          before = threading.active_count()
          for idx in range(10):
              response = await client.api_test()
              self.assertIsNotNone(response)
          after = threading.active_count()
          self.assertEqual(0, after - before)
  
  
subject: Add an integration test for #480