Python 3 conditioning for wskadmin. (#5013)

diff --git a/tools/admin/wskprop.py b/tools/admin/wskprop.py
index 8e9ef3f..3b1bd94 100644
--- a/tools/admin/wskprop.py
+++ b/tools/admin/wskprop.py
@@ -77,6 +77,6 @@
 
 def getPropertyValue(key, properties):
     evalue = os.environ.get(key)
-    value = (evalue if evalue is not None and evalue is not ''
+    value = (evalue if evalue != None and evalue != ''
              else properties[key] if key in properties else None)
     return value