Python for 3ds max - Replace selected objects with objects from an external file

max_replace_objects_from_disk.py

from MaxPlus import FileManager
from MaxPlus import SelectionManager

model_path = r"D:\Models\Some_model.max"

place_holders = []
for o in SelectionManager.Nodes:
     place_holders.append(o)

FileManager.Merge(model_path,True,True)

model = SelectionManager.GetNode(0)

for i in range(len(place_holders)):
     place_holders[i].SetObject(model.GetObject())
     place_holders[i].SetMaterial(model.GetMaterial())
     place_holders[i].SetName(model.Name + "_" + str(i))

model.Delete()