code: def test_get_extra_info(self):
      transport = asyncio.Transport({"extra": "info"})
      self.assertEqual("info", transport.get_extra_info("extra"))
      self.assertIsNone(transport.get_extra_info("unknown"))
  
      default = object()
      self.assertIs(
          default, transport.get_extra_info("unknown", default)
      )
  
file_path: cpython/Lib/test/test_asyncio/test_transports.py
imports: import unittest
  from unittest import mock
  import asyncio
  from asyncio import transports
label_desc: Use image node_id 2 for calling the TransportTests obj's underlying member method code with example usage: obj.test_get_extra_info() without return types