Unable to Access Object Properties, ObjectStamped is not Iterable

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Greetings.

Info

I am using:

Stacks/Packages

Turtlebot 3 w/ Jetson Nano
- LINUX UBUNTU 20.04, ROS NOETIC 1.15.14, ZED SDK (3.8.1) L4T 32.7 / JETPACK 4.6.1, CUDA 10.2
ZED 2i Camera

MASTER PC
- LINUX UBUNTU 20.04, ROS NOETIC 1.15.14, ZED SDK (3.8.1) UBUNTU 20.0 , CUDA 11.6

ENV VARIABLES

MASTER PC VARS
ROS_VERSION=1
ROS_PYTHON_VERSION=3
ROS_PACKAGE_PATH=/home/jsoltre1/catkin_ws/src:/opt/ros/noetic/share
ROSLISP_PACKAGE_DIRECTORIES=/home/jsoltre1/catkin_ws/devel/share/common-lisp
ROS_ETC_DIR=/opt/ros/noetic/etc/ros
ROS_MASTER_URI=http://192.168.0.28:11311
ROS_HOSTNAME=192.168.0.28
ROS_ROOT=/opt/ros/noetic/share/ros
ROS_DISTRO=noetic

TURTLEBOT VARS
ROS_VERSION=1
ROS_PYTHON_VERSION=3
ROS_PACKAGE_PATH=/opt/ros/noetic/share
ROSLISP_PACKAGE_DIRECTORIES=
ROS_ETC_DIR=/opt/ros/noetic/etc/ros
ROS_MASTER_URI=http://192.168.0.28:11311
ROS_HOSTNAME=192.168.0.30
ROS_ROOT=/opt/ros/noetic/share/ros
ROS_DISTRO=noetic

rospy, zed-ros-wrapper are my included packages used in this program.

Goal

I would like to make a simple program:

The turtlebot moves a linear distance, it looks for objects in it's field of view, and stops when it is near an object. - It finds an object. The Object's x position is used to defer the distance between the Turtlebot's Camera and the Object itself. - When the (moving) turtlebot crosses the threshold distance, the program will print a message and stop the robot's movement.

As of right now, I simply want the program to detect the object and return a message that states "Object (x), detect, position close by.".

MY CODE:

#! /usr/bin/env python3

from queue import Empty
from re import X
from shutil import move
from tkinter import Y
from turtle import distance, forward, position, speed

from numpy import empty
import rospy
#from geometry_msgs.msg import Twist, Point
#from nav_msgs.msg import Odometry
from zed_interfaces.msg import Object
from zed_interfaces.msg import ObjectsStamped

objects = ObjectsStamped()
postObjx = Object()

def callback(msg):
    while not rospy.is_shutdown():
        objXThreshold = 2.0

        for i in objects:
            if (objects[i].position[0] >= objThreshold):
                print("Object" + str(objects[i].label) + "detected, position close by.")

def listenerObjX():

    rospy.init_node('listenerObjx', anonymous = True)
    subObjlist = rospy.Subscriber('/zed2i/zed_node/obj_det/objects', ObjectsStamped, callback)
    #subZedOdom = rospy.Subscriber('/zed2i/zed_node/odom', callback)
    rospy.spin()

if __name__ == '__main__':
    listenerObjX()

Issue

MY CODE ERROR:

[ERROR] [1667845398.329518]: bad callback: <function callback at 0x7f5e1b22a280>
Traceback (most recent call last):
  File "/opt/ros/noetic/lib/python3/dist-packages/rospy/topics.py", line 750, in _invoke_callback
    cb(msg)
  File "turtlebotLinearObjDet.py", line 23, in callback
    for i in objects:
TypeError: 'ObjectsStamped' object is not iterable

I am confused.

The topic ObjectsStamped is to be an array that stores Objects that are seen and captured by the ZED Camera, and sent to the zed_ros_wrapper as information. The topic Object, holds the unique properties of x, y, z and etc. As found in the ZED SDK's documentation.

https://www.stereolabs.com/docs/ros/o...

How might I be able to access ObjectsStamped and ... (more)