Features: 1) Add retry mechanism with exponential backoff for saving attributes to handle deadlocks.

Fixes: 1) Remove unused `traceback` import; 2) Add missing import for `OperationalError`; 3) Prevent redundant saves for unchanged attributes.

Extra: 1) Simplify attribute save logic and improve efficiency; 2) Code cleanup for better readability.

core/vendors/__init__.py

@@ -1,6 +1,6 @@
 import gzip
 import json
-import traceback
+import time
 from contextlib import suppress
 from datetime import datetime
 from decimal import Decimal
@@ -14,6 +14,7 @@ from django.conf import settings
 from django.core.files.base import ContentFile
 from django.db import IntegrityError, transaction
 from django.db.models import QuerySet
+from django.db.utils import OperationalError
 
 from core.elasticsearch import process_system_query
 from core.models import (
@@ -446,15 +447,27 @@ class AbstractVendor:
             )
         except Attribute.MultipleObjectsReturned:
             attribute = Attribute.objects.filter(name=key, group=attr_group).order_by("uuid").first()  # type: ignore [assignment]
+            fields_to_update: list[str] = []
+            if not attribute.is_active:
                 attribute.is_active = True
+                fields_to_update.append("is_active")
+            if attribute.value_type != attr_value_type:
                 attribute.value_type = attr_value_type
-            attribute.save()
+                fields_to_update.append("value_type")
+            if fields_to_update:
+                for attempt in range(5):
+                    try:
+                        attribute.save(update_fields=fields_to_update)
+                        break
+                    except OperationalError as e:
+                        if "deadlock detected" in str(e):
+                            time.sleep(0.1 * (2**attempt))
+                            continue
+                        raise
         except IntegrityError:
             async_logger.warning(f"IntegrityError while processing attribute {key!r}...")
             return
 
-        attribute.save()
-
         if not is_created:
             return