NameError: name 'Combobox' is not defined

#!/usr/bin/env python2.7
import paramiko
from paramiko import SSHClient
from tkinter import *
import os
 
Directory=os.getcwd()
 
ssh = SSHClient()
ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
ssh.load_system_host_keys()
ssh.connect(host, username=user, password=secret)
transport = paramiko.Transport((host, port))
transport.connect(username=user, password=secret)
#sftp = ssh.open_sftp()
sftp = paramiko.SFTPClient.from_transport(transport)
 
def poisk():
    a = "1598002389"
    a = EntryA.get() # берем текст из первого поля
    x = combo.get()
    remotepath ='../opt/logs/' + x +"//"
    localpath  = Directory + "\\" + a.rstrip() + ".txt"   
    a =".*" + a.rstrip()
    serverfilelist = sftp.listdir(remotepath)
    serverfilelist.sort
    print(a)
    for s in serverfilelist:
        if re.search(a, s):
            remotepath = remotepath +s
            print(remotepath)
            sftp.get(remotepath, localpath)
            print(localpath)
            break
               
Windows1 = Tk()
Windows1.title('Проверка статуса')
 
Label(Windows1, text='').grid(row=0, sticky=W)
lbl3 = Label(Windows1, text='Результат')
lbl3.grid(row=3, sticky=W) 
 
EntryA = Entry(Windows1, width=30, font='Arial 8')
EntryA.insert(0, "1598002389")
EntryA.grid(row=0, column=1, sticky=E)
 
combo = Combobox(Windows1)  
combo['values'] = ("test","ROBOT")  
combo.current(1)  # установите вариант по умолчанию  
combo.grid(column=1, row=4)  
 
but = Button(Windows1, text='Проверка', command=poisk)
but.grid(row=3, column=1, sticky=E)
 
Windows1.mainloop()  #ожидание закрытия приложения      
ssh.close()

import tkinter as tk
from tkinter import ttk
 
root = tk.Tk() 
example = ttk.Combobox(root, values=["1", "2", "3"])