test_concat_gctoo.py: use __future__.print_function import

Author: mruffalo

cmapPy/pandasGEXpress/tests/test_concat_gctoo.py

@@ -1,3 +1,5 @@
+from __future__ import print_function
+
 import os
 import unittest
 import logging
@@ -369,9 +371,9 @@ def parse_args(self, unused):
 
         os.remove(expected_output_file)
 
-        print
-        print
-        print
+        print()
+        print()
+        print()
 
         #happy path
         args.remove_all_metadata_fields = True