Fix python3 syntax error.
Fix python3 syntax error.

pebble/pebble-tool,pebble/pebble-tool,gregoiresage/pebble-tool,gregoiresage/pebble-tool,pebble/pebble-tool,gregoiresage/pebble-tool,pebble/pebble-tool,gregoiresage/pebble-tool