diff --git a/sensor/DS18B20.py b/sensor/DS18B20.py
index 82930f4..5019cdc 100644
--- a/sensor/DS18B20.py
+++ b/sensor/DS18B20.py
@@ -27,6 +27,7 @@
 
 import subprocess
 import sensor
+import time
 from sensor.util import Temperature
 
 class DS18B20(sensor.SensorBase):