diff --git a/csla_binary/binary_writer.py b/csla_binary/binary_writer.py
index daeee28..beefe74 100644
--- a/csla_binary/binary_writer.py
+++ b/csla_binary/binary_writer.py
@@ -14,6 +14,7 @@
# You should have received a copy of the GNU Affero General Public License
# along with this program. If not, see .
+from datetime import datetime
from decimal import Decimal
import io
import struct
@@ -85,6 +86,10 @@ class CslaBinaryWriter:
# BinaryWriter.WriteInt32
self.stream.write(struct.pack('