[Python] Fix relative path for model files and dirs

python/display.py

 import unittest
 import pinocchio as se3
 import numpy as np
+import os
 
 from pinocchio.robot_wrapper import RobotWrapper
 
 # Warning : the paths are here hard-coded. This file is only here as an example
-list_py = ["/local/fvalenza/devel/src/pinocchio/models","titi"]
-robot = RobotWrapper("/local/fvalenza/devel/src/pinocchio/models/romeo.urdf",list_py, se3.JointModelFreeFlyer())
+romeo_model_path = os.path.abspath(os.path.join(current_file, '../models'))
+romeo_model_file = romeo_model_path + "/romeo.urdf"
+
+list_hints = [romeo_model_path,"titi"]
+robot = RobotWrapper(romeo_model_file,list_hints, se3.JointModelFreeFlyer())
 
 robot.initDisplay()
 robot.loadDisplayModel("world/pinocchio")