diff --git a/PercutaneousApproachAnalysis/PercutaneousApproachAnalysis.py b/PercutaneousApproachAnalysis/PercutaneousApproachAnalysis.py
index 2d69e26..ca90dfa 100644
--- a/PercutaneousApproachAnalysis/PercutaneousApproachAnalysis.py
+++ b/PercutaneousApproachAnalysis/PercutaneousApproachAnalysis.py
@@ -3,7 +3,7 @@
 from __main__ import vtk, qt, ctk, slicer
 import time
 import math
-
+import string
 
 class PercutaneousApproachAnalysis:
   def __init__(self, parent):