Add Random Object

add_random_object.py

import bpy
import random

bl_info = {
    'name': 'Add Random Object',
    'version': (0, 0, 0),
    'blender': (2, 5, 9),
    'category': 'Object',
    'description': 'Pick a random object and add it at the cursor',
}

def find_settings():
    screen = bpy.data.screens.get('Default', bpy.data.screens[0])
    try:
        settings = screen.random_object_tools_settings
    except:
        settings = None
    
    return settings

class AddRandomObject(bpy.types.Operator):
    bl_idname = 'object.add_random'
    bl_label = 'Add Random Object'
    bl_options = {'REGISTER', 'UNDO'}
    bl_description = 'Add random object.'

    def execute(self, context):
        screen = bpy.data.screens['Default']
        settings = screen.random_object_tools_settings
        group = bpy.data.groups[settings.group]
        objects = group.objects.values()
        source = random.choice(objects)
        bpy.ops.object.select_all(action='DESELECT')
        bpy.ops.object.add(type='MESH', location=context.scene.cursor_location)
        dest = bpy.context.active_object
        dest.name = source.name
        dest.data = source.data
        return {'FINISHED'}

class AddRandomObjectTools(bpy.types.Panel):
    bl_label = 'Add Random Object Tools'
    bl_idname = 'OBJECT_PT_add_random_object_tools'
    bl_space_type = 'VIEW_3D'
    bl_region_type = 'UI'

    def draw(self, context):
        layout = self.layout
        settings = find_settings()
        row = layout.row()
        row.prop(settings, 'group')

class AddRandomObjectToolsSettings(bpy.types.PropertyGroup):
    group = bpy.props.StringProperty(name='Group name')
        
def menu_func():
    self.layout.operator(AddRandomObject.bl_idname, text="Add Random Object")

def register():
    bpy.utils.register_module(__name__)
    bpy.types.VIEW3D_MT_object_specials.append(menu_func)
    bpy.types.Screen.random_object_tools_settings = \
        bpy.props.PointerProperty(type=AddRandomObjectToolsSettings)

def unregister():
    bpy.utils.unregister_module(__name__)
    bpy.types.VIEW3D_MT_object_specials.remove(menu_func)

if __name__ == "__main__":
    register()