Have generator run only once

[topquarkone]

Hi - I am using a generator to add objects along a spline, via a script in Unity edit mode. This works fine: when I run the script, generators get placed in the hierarchy, and the objects are created correctly.  However, it turns out that every time I play the game, these objects get generated again. How can I stop a generator from running during Play? I only want them to run once, in the editor, when I am putting together the scene.