style fixes

Author: vgvoleg

examples/query-service/basic_example.py

@@ -18,6 +18,7 @@ def main():
     # session = client.session().create()
     pool = ydb.QuerySessionPool(driver)
     # with pool.checkout() as session:
+    
     def callee(session):
         print("=" * 50)
         print("BEFORE ACTION")

ydb/query/__init__.py

@@ -7,13 +7,13 @@
 from .session import QuerySessionSync
 
 from .._grpc.grpcwrapper.ydb_query_public_types import (
-    QueryOnlineReadOnly,
-    QuerySerializableReadWrite,
-    QuerySnapshotReadOnly,
-    QueryStaleReadOnly,
+    QueryOnlineReadOnly,  # noqa
+    QuerySerializableReadWrite,  # noqa
+    QuerySnapshotReadOnly,  # noqa
+    QueryStaleReadOnly,  # noqa
 )
 
-from .pool import QuerySessionPool
+from .pool import QuerySessionPool  # noqa
 
 
 class QueryClientSync(IQueryClient):

ydb/query/pool.py

@@ -1,11 +1,9 @@
-import abc
 import time
 from typing import Callable
 
 from . import base
 from .session import (
     QuerySessionSync,
-    BaseQuerySession,
 )
 from .. import issues
 from .._errors import check_retriable_error