Fix show output for data members
diff --git a/tools/pylibopenflow/pylib/cpythonize.py b/tools/pylibopenflow/pylib/cpythonize.py
index 89c9a84..22b5214 100644
--- a/tools/pylibopenflow/pylib/cpythonize.py
+++ b/tools/pylibopenflow/pylib/cpythonize.py
@@ -470,7 +470,7 @@
             elif (isinstance(member, cheader.cstruct)):
                 code.append(self.tab*2 + "outstr += prefix + '" + 
                             member.name + ": \\n' ")
-                code.append(self.tab*2 + "self." + member.name + 
+                code.append(self.tab*2 + "outstr += self." + member.name + 
                             ".show(prefix + '  ')")
             elif (isinstance(member, cheader.carray) and
                   not isinstance(member.object, cheader.cprimitive)):