code: def test_register_plugin(self):
      with self.assertLogs(level="WARNING") as log_output:
          with mock.patch.object(
              xc, "load_pjrt_plugin_dynamically", autospec=True
          ):
              if platform.system() == "Windows":
                  os.environ[
                      "PJRT_NAMES_AND_LIBRARY_PATHS"
                  ] = "name1;path1,name2;path2,name3"
              else:
                  os.environ[
                      "PJRT_NAMES_AND_LIBRARY_PATHS"
                  ] = "name1:path1,name2:path2,name3"
              with mock.patch.object(
                  xc.profiler, "register_plugin_profiler", autospec=True
              ):
                  xb.register_pjrt_plugin_factories_from_env()
      registration = xb._backend_factories["name1"]
      with mock.patch.object(
          xc, "make_c_api_client", autospec=True
      ) as mock_make:
          with mock.patch.object(
              xc,
              "pjrt_plugin_initialized",
              autospec=True,
              return_vale=True,
          ):
              with mock.patch.object(
                  xc, "initialize_pjrt_plugin", autospec=True
              ):
                  registration.factory()
  
      self.assertRegex(
          log_output[1][0],
          r"invalid value name3 in env var PJRT_NAMES_AND_LIBRARY_PATHS"
          r" name1.path1,name2.path2,name3",
      )
      self.assertIn("name1", xb._backend_factories)
      self.assertIn("name2", xb._backend_factories)
      self.assertEqual(registration.priority, 400)
      self.assertTrue(registration.experimental)
      mock_make.assert_called_once_with("name1", None, None)
  
imports: import os
  import platform
  import time
  import warnings
  from absl import logging
  from absl.testing import absltest
  from jax._src import compiler
  from jax._src import config
  from jax._src import test_util
  from jax._src import xla_bridge
  from jax._src.interpreters import xla
  from jax._src.lib import xla_client
label_desc: Use image node_id 10 for calling the XlaBridgeTest obj's underlying member method code with example usage: obj.test_register_plugin() without return types