From ec0f21ef8e1af28eeb06c8ca3636163466585b09 Mon Sep 17 00:00:00 2001
From: Tsuyoshi Hombashi <gogogo.vm@gmail.com>
Date: Sun, 8 Jan 2017 11:30:02 +0900
Subject: [PATCH] Add an import

---
 dataproperty/__init__.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/dataproperty/__init__.py b/dataproperty/__init__.py
index 424e238..91e6321 100644
--- a/dataproperty/__init__.py
+++ b/dataproperty/__init__.py
@@ -44,6 +44,7 @@
 from ._type import (
     NoneType,
     StringType,
+    NullStringType,
     IntegerType,
     FloatType,
     DateTimeType,