fix import errors in Session.py and SessionExample.py

client-py/src/SessionExample.py

@@ -19,7 +19,8 @@
 # Uncomment the following line to use apache-iotdb module installed by pip3
 
 from iotdb.Session import Session
-from iotdb.utils import Tablet
+from iotdb.utils.Tablet import Tablet
+from iotdb.utils.IoTDBConstants import *
 
 # creating session connection.
 ip = "127.0.0.1"

client-py/src/iotdb/Session.py

@@ -20,7 +20,8 @@ import struct
 import sys
 import time
 
-from .utils import SessionDataSet
+from .utils.SessionDataSet import SessionDataSet
+from .utils.IoTDBConstants import *
 
 from thrift.protocol import TBinaryProtocol, TCompactProtocol
 from thrift.transport import TSocket, TTransport