How to subscribe to multiple topic that has no header or how to add header into topics?

edit

ROS Kinetic Ubuntu 16.04 Python 3.5.2

I am trying to use following script to subscribe to 2 topics and combining their data into a json file.

import rospy
from std_msgs.msg import Float32
import message_filters
import json

def callback(rwheel, lwheel):
   # merging rwheel.data and lwheel.data into a json file

def listener():
   rospy.init_node('node_name')
   rwheel = message_filters.Subscriber("rwheel_angular_vel_motor", Float32)
   lwheel = message_filters.Subscriber("lwheel_angular_vel_motor", Float32)
   ts = message_filters.TimeSynchronizer([rwheel,lwheel], 10)
   ts.registerCallback(callback)
   rospy.spin()

if __name__ == '__main__':
  listener();

When I run the script, I am gettin the folowing error:

[ERROR] [1573630972.895704, 1242.480000]: bad callback: <bound method Subscriber.callback of <message_filters.Subscriber object at 0x7fd23d298278>>
Traceback (most recent call last):
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/rospy/topics.py", line 750, in _invoke_callback
    cb(msg)
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/message_filters/__init__.py", line 75, in callback
    self.signalMessage(msg)
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/message_filters/__init__.py", line 57, in signalMessage
    cb(*(msg + args))
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/message_filters/__init__.py", line 216, in add
    my_queue[msg.header.stamp] = msg
AttributeError: 'Float32' object has no attribute 'header"

Acually, error seems pretty straight forward. 'Float32' object has no attribute 'header' so we have to add header to Float32 but I couldn't figure out how to do. So, is there a way to subscribe mutiple topics wihout header or how can we add a header?