py36 Import error bug fix (#41135)

* lazy import

* log error

python/paddle/distributed/ps/the_one_ps.py

@@ -15,7 +15,6 @@
 import warnings
 
 import os
-import paddle.distributed.fleet.proto.the_one_ps_pb2 as ps_pb2
 import paddle.fluid as fluid
 import paddle.distributed.fleet as fleet
 from paddle.fluid import core
@@ -27,6 +26,7 @@ from paddle.fluid.parallel_executor import ParallelExecutor
 from paddle.fluid.framework import Variable, Parameter
 from paddle.distributed.fleet.runtime.runtime_base import RuntimeBase
 from paddle.distributed.fleet.base.private_helper_function import wait_server_ready
+import paddle.distributed.fleet.proto.the_one_ps_pb2 as ps_pb2
 from paddle.fluid.communicator import Communicator, HeterClient
 from google.protobuf import text_format
 

python/paddle/distributed/ps/utils/public.py

@@ -59,7 +59,8 @@ DATA_NORM_GRAD_NAME = [x + "@GRAD" for x in DATA_NORM_NAME]
 def logger_config(log_path, logging_name):
     logger = logging.getLogger(logging_name)
     logger.setLevel(level=logging.DEBUG)
-    handler = logging.FileHandler(log_path, mode='a', encoding='UTF-8')
+    handler = logging.FileHandler(
+        log_path, mode='a', encoding='UTF-8', delay=True)
     handler.setLevel(logging.INFO)
     formatter = logging.Formatter(
         '%(levelname)s - %(asctime)s - %(pathname)s: %(lineno)s - %(message)s')