base: First pass at making nag-once working with python3

Signed-off-by: Pierre-Yves Chibon <pingou@pingoured.fr>

roles/base/files/common-scripts/nag-once

@@ -7,6 +7,7 @@
 # copyright (c) 2011 Red Hat, inc
 # gpl v2 blah blah
 # skvidal - skvidal@fedoraproject.org 
+from __future__ import print_function
 
 import tempfile
 import sys
@@ -86,23 +87,23 @@ def main():
         
         if theinput != old_output or (tti and now - old_date > tti):
             if theinput.strip(): # if there is nothing here, don't output and don't drop a \n on the end of it
-                 print theinput,
+                 print(theinput,)
             fo = open(mydir + '/output', 'w')
             fo.write(theinput)
             fo.flush()
             fo.close()
         
         
-    except Exception, e:
-        print >> sys.stderr, e
-        print >> sys.stderr, theinput
+    except Exception as e:
+        print(e, file=sys.stderr)
+        print(theinput, file=sys.stderr)
 
 if __name__ == '__main__':
     try:
         main()
-    except Exception, e:
-        print >> sys.stderr, e
+    except Exception as e:
+        print(e, file=sys.stderr)
         if not sys.stdin.isatty():
-            print >> sys.stderr, sys.stdin.read()
+            print(sys.stdin.read(), file=sys.stderr)