how to operate simulation in gazebo through virtual keyboard via ros?

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i have build a keyboard with tkinter & python with 4 buttons and i want to operate my simulation through that keys i want to modify teleop_twist_keyboard will attche files below

keyboard.py

#!/usr/bin/python3

#
#
##################################################
######## Please Don't Remove Author Name #########
############### Thanks ###########################
##################################################
#
#
__author__='Kuldeep Wadaskar'

######################################################

######################################################
Kuldeep Wadaskar, 3NOT ROBOTICS PVT LTd,
www.3notrobotics.in

######################################################


# import modules
try:
    import Tkinter
except:
    import tkinter as Tkinter

import pyautogui

keys =[ 
[
# =========================================
# ===== Keyboard Configurations ===========
# =========================================

 [
  # Layout Name
  ("Function_Keys"),

  # Layout Frame Pack arguments
  ({'side':'top','expand':'yes','fill':'both'}),
  [
   # list of Keys
   ('esc'," ", 'F1', 'F2','F3','F4',"",'F5','F6','F7','F8',"",'F9','F10','F11','F12')
  ]
 ],

 [
  ("Character_Keys"),
  ({'side':'top','expand':'yes','fill':'both'}),
  [
   ('~\n`','!\n1','@\n2','#\n3','$\n4','%\n5','^\n6','&\n7','*\n8','(\n9',')\n0','_\n-','+\n=','|\n\\','backspace'),
   ('tab','q','w','e','r','t','y','u','i','o','p','{\n[','}\n]','   '),
   ('capslock','a','s','d','f','g','h','j','k','l',':\n;',"\"\n'","enter"),
   ("shift",'z','x','c','v','b','n','m','<\n,','>\n.','?\n/',"shift"),
   ("ctrl", "[+]",'alt','\t\tspace\t\t','alt','[+]','[=]','ctrl')
  ]
 ]
],
[
 [
  ("System_Keys"),
  ({'side':'top','expand':'yes','fill':'both'}),
  [
   (
    "print\nscreen\nsys",
    "scroll\nlock",
    "pause\nbreak"
   )
  ]
 ],
 [
  ("Editing_Keys"),
  ({'side':'top','expand':'yes','fill':'both'}),
  [
   (
    "insert",
    "home",
    "page\nup"
    ),
   ( "delete",
    "end",
    "page\ndown"
    ),
  ]
 ],

 [
  ("Navigation_Keys"),
  ({'side':'top','expand':'yes','fill':'both'}),
  [
   (
    "up",
    ),
   ( "right",
    "down",
    "left"
    ),
  ]
 ],

],
[

 [
  ("Numeric_Keys"),
  ({'side':'top','expand':'yes','fill':'both'}),
  [
   ("num\nlock","/","*","-"),
   ("7","8","9","+"),
   ("4","5","6"," "),
   ("0","1","2","3"),
   ("0",".","enter")
  ]
 ],

]

]

##  Frame Class
class Keyboard(Tkinter.Frame):
 def __init__(self, *args, **kwargs):
  Tkinter.Frame.__init__(self, *args, **kwargs)

  # Function For Creating Buttons
  self.create_frames_and_buttons()

 # Function For Extracting Data From KeyBoard Table
 # and then provide us a well looking
 # keyboard gui
 def create_frames_and_buttons(self):
  # take section one by one
  for key_section in keys:
   # create Sperate Frame For Every Section
   store_section = Tkinter.Frame(self)
   store_section.pack(side='left',expand='yes',fill='both',padx=10,pady=10,ipadx=10,ipady=10)

   for layer_name, layer_properties, layer_keys in key_section:
    store_layer = Tkinter.LabelFrame(store_section)#, text=layer_name)
    #store_layer.pack(side='top',expand='yes',fill='both')
    store_layer.pack(layer_properties)
    for key_bunch in layer_keys:
     store_key_frame = Tkinter.Frame(store_layer)
     store_key_frame.pack(side='top',expand='yes',fill='both')
     for k in key_bunch:
      k=k.capitalize()
      if len(k)<=3:
       store_button = Tkinter.Button(store_key_frame, text=k, width=2, height=2)
      else:
       store_button = Tkinter.Button(store_key_frame, text=k.center(5,' '), height=2)
      if " " in k:
       store_button['state']='disable'
      #flat, groove, raised, ridge, solid, or sunken
      store_button['relief']="sunken"
      store_button['bg']="powderblue"
      store_button['command']=lambda q=k: self.button_command(q)
      store_button.pack(side='left',fill='both',expand='yes')
  return

  # Function For Detecting Pressed Keyword.
 def button_command(self, event):
  print (event)
  return

# Creating Main Window
def main():
 root = Tkinter.Tk(className=" Python Virtual KeyBoard")
 Keyboard(root).pack()
 root.mainloop()
 return

# Function Trigger
if __name__=='__main__':
 main()

teleop_twist_keyboard.py

#!/usr/bin/env python

from __future__ import print_function

import roslib; roslib.load_manifest('teleop_twist_keyboard')
import rospy

from geometry_msgs.msg import Twist

import sys, select, termios, tty

msg = """
Reading from the keyboard  and Publishing to Twist!
---------------------------
Moving around:
   u    i    o
   j    k    l
   m    ,    .

For Holonomic ...