code: def test_sendfile_for_closing_transp(self):
      srv_proto, cli_proto = self.prepare_sendfile()
      cli_proto.transport.close()
      with self.assertRaisesRegex(RuntimeError, "is closing"):
          self.run_loop(
              self.loop.sendfile(cli_proto.transport, self.file)
          )
      self.run_loop(srv_proto.done)
      self.assertEqual(srv_proto.nbytes, 0)
      self.assertEqual(self.file.tell(), 0)
  
imports: import asyncio
  import errno
  import os
  import socket
  import sys
  import tempfile
  import unittest
  from asyncio import base_events
  from asyncio import constants
  from unittest import mock
  from test import support
  from test.support import os_helper
  from test.support import socket_helper
  from test.test_asyncio import utils
label_desc: Use image node_id 7 for calling the SendfileMixin obj's underlying member method code with example usage: obj.test_sendfile_for_closing_transp() without return types