diff --git a/bifacialvf/bifacialvf.py b/bifacialvf/bifacialvf.py
index 8b29aaa..e01f2c0 100644
--- a/bifacialvf/bifacialvf.py
+++ b/bifacialvf/bifacialvf.py
@@ -25,14 +25,14 @@
 import math
 import csv
 import pvlib
-import os, sys
+import os
 
 from vf import getBackSurfaceIrradiances, getFrontSurfaceIrradiances, getGroundShadeFactors
 from vf import getSkyConfigurationFactors, trackingBFvaluescalculator, rowSpacing
 from sun import hrSolarPos, perezComp, solarPos, sunIncident
 import pandas as pd
 
-#from builtins import str, range
+
 
 def simulate(TMYtoread, writefiletitle,  beta = 0, sazm = 180, C = 0.5, D = None,
              rowType = 'interior', transFactor = 0.01, cellRows = 6, 
diff --git a/bifacialvf/loadVFresults.py b/bifacialvf/loadVFresults.py
index 76e0e4b..18a07aa 100644
--- a/bifacialvf/loadVFresults.py
+++ b/bifacialvf/loadVFresults.py
@@ -5,7 +5,7 @@
 
 
 """
-from __future__ import division, print_function, unicode_literals
+from __future__ import division, print_function # ensure python3 compatible division and printing
 import io
 try:
     from urllib2 import urlopen