Remove deprecated PubSub (#9039)

Author: fjetter

distributed/__init__.py

@@ -58,7 +58,6 @@
 from distributed.lock import Lock
 from distributed.multi_lock import MultiLock
 from distributed.nanny import Nanny
-from distributed.pubsub import Pub, Sub
 from distributed.queues import Queue
 from distributed.scheduler import KilledWorker, Scheduler
 from distributed.security import Security
@@ -117,7 +116,6 @@ def __getattr__(name):
     "NannyPlugin",
     "InstallPlugin",
     "PipInstall",
-    "Pub",
     "Queue",
     "Reschedule",
     "SSHCluster",
@@ -127,7 +125,6 @@ def __getattr__(name):
     "Semaphore",
     "SpecCluster",
     "Status",
-    "Sub",
     "SubprocessCluster",
     "TimeoutError",
     "UploadDirectory",

distributed/client.py

@@ -92,7 +92,6 @@
 from distributed.protocol.pickle import dumps, loads
 from distributed.protocol.serialize import _is_dumpable
 from distributed.publish import Datasets
-from distributed.pubsub import PubSubClientExtension
 from distributed.security import Security
 from distributed.sizeof import sizeof
 from distributed.spans import SpanMetadata
@@ -134,9 +133,7 @@
 
 _current_client: ContextVar[Client | None] = ContextVar("_current_client", default=None)
 
-DEFAULT_EXTENSIONS = {
-    "pubsub": PubSubClientExtension,
-}
+DEFAULT_EXTENSIONS: dict[str, Any] = {}
 
 TOPIC_PREFIX_FORWARDED_LOG_RECORD = "forwarded-log-record"