Blender Script to continuously animate cubes of different heights

animate_cube.py

import bpy
import random

def my_animator(scene):
    print("Frame change", scene.frame_current)
    if scene.frame_current == 100:
        bpy.ops.object.delete()
        
        bpy.ops.mesh.primitive_cube_add(scale = (1, 1, 1 + random.uniform(0, 2.0)))
        cube = bpy.context.active_object
        cube.location.x = 10
        cube.keyframe_insert("location", frame=1)
        cube.location.x = -10
        cube.keyframe_insert("location", frame=100)        
        

bpy.app.handlers.frame_change_pre.clear()
bpy.app.handlers.frame_change_pre.append(my_animator)