diff --git a/processing/post/addCompatibilityMismatch.py b/processing/post/addCompatibilityMismatch.py
index 553fa9390..8aff13c53 100755
--- a/processing/post/addCompatibilityMismatch.py
+++ b/processing/post/addCompatibilityMismatch.py
@@ -1,8 +1,8 @@
 #!/usr/bin/env python3
 
 import os
-import math
 import sys
+from io import StringIO
 from optparse import OptionParser
 
 import numpy as np
@@ -61,10 +61,10 @@ def volTetrahedron(coords):
 
 def volumeMismatch(size,F,nodes):
   """
-  Calculates the volume mismatch
+  Calculates the volume mismatch.
   
   volume mismatch is defined as the difference between volume of reconstructed 
-  (compatible) cube and determinant of defgrad at the FP
+  (compatible) cube and determinant of deformation gradient at Fourier point.
   """
   coords = np.empty([8,3])
   vMismatch = np.empty(grid[::-1])
@@ -97,11 +97,11 @@ def volumeMismatch(size,F,nodes):
 
 def shapeMismatch(size,F,nodes,centres):
   """
-  Routine to calculate the shape mismatch
+  Routine to calculate the shape mismatch.
   
   shape mismatch is defined as difference between the vectors from the central point to
   the corners of reconstructed (combatible) volume element and the vectors calculated by deforming
-  the initial volume element with the  current deformation gradient
+  the initial volume element with the  current deformation gradient.
   """
   coordsInitial = np.empty([8,3])
   sMismatch    = np.empty(grid[::-1])
diff --git a/processing/post/addIPFcolor.py b/processing/post/addIPFcolor.py
index 5114b6a91..014b0147d 100755
--- a/processing/post/addIPFcolor.py
+++ b/processing/post/addIPFcolor.py
@@ -2,6 +2,7 @@
 
 import os
 import sys
+from io import StringIO
 from optparse import OptionParser
 
 import numpy as np
diff --git a/processing/post/addNorm.py b/processing/post/addNorm.py
index e58947de0..4ac2bf899 100755
--- a/processing/post/addNorm.py
+++ b/processing/post/addNorm.py
@@ -2,6 +2,7 @@
 
 import os
 import sys
+from io import StringIO
 from optparse import OptionParser
 
 import numpy as np
diff --git a/processing/post/addPole.py b/processing/post/addPole.py
index 9f4982ff5..58f9235dc 100755
--- a/processing/post/addPole.py
+++ b/processing/post/addPole.py
@@ -2,6 +2,7 @@
 
 import os
 import sys
+from io import StringIO
 from optparse import OptionParser
 
 import numpy as np