RTU: relocate OperationError

Author: dandavison

temporalio/worker/_nexus.py

@@ -306,7 +306,7 @@ async def _start_operation(
                         "nexusrpc.handler.StartOperationResultAsync."
                     )
                 )
-        except nexusrpc.handler.OperationError as err:
+        except nexusrpc.OperationError as err:
             return temporalio.api.nexus.v1.StartOperationResponse(
                 operation_error=await self._operation_error_to_proto(err),
             )
@@ -332,7 +332,7 @@ async def _exception_to_failure_proto(
 
     async def _operation_error_to_proto(
         self,
-        err: nexusrpc.handler.OperationError,
+        err: nexusrpc.OperationError,
     ) -> temporalio.api.nexus.v1.UnsuccessfulOperationError:
         cause = err.__cause__
         if cause is None:

tests/nexus/test_handler.py

@@ -27,15 +27,13 @@
 import httpx
 import nexusrpc
 import pytest
-from nexusrpc import OperationInfo
+from nexusrpc import OperationError, OperationErrorState, OperationInfo
 from nexusrpc.handler import (
     CancelOperationContext,
     FetchOperationInfoContext,
     FetchOperationResultContext,
     HandlerError,
     HandlerErrorType,
-    OperationError,
-    OperationErrorState,
     OperationHandler,
     StartOperationContext,
     service_handler,