Python: Randomly selecting 1 object in a set

Question

I have a set up like this:

Where there are 3 or sometimes more grids of different objects one behind the other. The objects are regularly spaced around 20 units in each axis, tho their origins are not always at a regular point. I need to select an even amount of objects from each of the grids so that I can merge them into a single grid with all the types of objects.

I have these code from another question I made that creates 20x20x80 cells and merges the objects inside of them:

import bpy

# grid layout in space
cell_offset = (-10, -40, -10)
cell_size = (20, 80, 20)

# little helper to snap values to a grid
def snap(val, step):
    return (val//step) * step

objects = bpy.data.collections["Collection"].objects # take from a collection
#objects = bpy.context.selected_objects  # or take selected objects

cells = {}
for obj in objects:
    # snap the object's location to the next lower cell corner
    key = (
        snap(obj.location.x - cell_offset[0], cell_size[0]),
        snap(obj.location.y - cell_offset[1], cell_size[1]),
        snap(obj.location.z - cell_offset[2], cell_size[2])
    )
    # group objects with the same cell
    if key not in cells:
        cells[key] = [obj]
    else:
        cells[key].append(obj)

# select all objects in one cell and join them
for value in cells.values():
    bpy.ops.object.select_all(action='DESELECT')
    
    if len(value) > 1: # joining makes sense
        bpy.context.view_layer.objects.active = value[0]
        for obj in value:
            obj.select_set(True)

        bpy.ops.object.join()
        
        


        
        

Is there a way to tell it to select 1 of the objects in each cell at random instead of merging them?

I assume the code would help but if it has to be done differently that's also fine.

Answer 1

Notwithstanding the first part of your script which is irrelevant to your actual question, you can select a random item from a sequence with the standard random.choice function that comes with the python standard random module. This is arguably not really a Blender question but rather a Python question, but here goes :

import random

# The first part of your script...

bpy.ops.object.select_all(action='DESELECT')
for objects in cells.values():
    random.choice(objects).select_set(True)