FBX export fetch meshes (1)...
TypeError: an integer is required (got type NoneType)
Traceback (most recent call last):
  File "C:\Desktop\blender-2.79.0-git.d0920fb-windows64\2.79\scripts\addons\io_scene_fbx\__init__.py", line 620, in execute
    return export_fbx_bin.save(self, context, **keywords)
  File "C:\Desktop\blender-2.79.0-git.d0920fb-windows64\2.79\scripts\addons\io_scene_fbx\export_fbx_bin.py", line 3113, in save
    ret = save_single(operator, context.scene, filepath, **kwargs_mod)
  File "C:\Desktop\blender-2.79.0-git.d0920fb-windows64\2.79\scripts\addons\io_scene_fbx\export_fbx_bin.py", line 3020, in save_single
    fbx_objects_elements(root, scene_data)
  File "C:\Desktop\blender-2.79.0-git.d0920fb-windows64\2.79\scripts\addons\io_scene_fbx\export_fbx_bin.py", line 2819, in fbx_objects_elements
    fbx_data_mesh_elements(objects, me_obj, scene_data, done_meshes)
  File "C:\Desktop\blender-2.79.0-git.d0920fb-windows64\2.79\scripts\addons\io_scene_fbx\export_fbx_bin.py", line 941, in fbx_data_mesh_elements
    me.polygons.foreach_get("use_smooth", t_ps)
TypeError: couldn't access the py sequence

location: <unknown location>:-1

location: <unknown location>:-1