Окно с несколькими полями ввода и присвоение переменных

from Tkinter import *
import tkMessageBox
import ttk
import math
import sys
 
def placement001(iix,iiy):
    lbl.place(x=(iix*105)+20,y=(iiy*70)+25)
def placement002(iix,iiy):
    btn.place(x=(iix*105)+20,y=(iiy*70)+25)
def placement003(iix,iiy):
    txt.place(x=(iix*105)+20,y=(iiy*70)+25)
def clicked():
    res="L={}".format(txt.get())
    lbl.configure(text=res,font=("arial bold",16),fg="black")
    placement001(3,2)
 
window=Tk()
window.title('test002')
 
lbl=Label(window,text="Inductance",font=("Arial Bold",16),fg="black")
placement001(2,0)
window.geometry('750x550')
lbl=Label(window,text="L=",font=("Arial Bold",16),fg="black")
placement001(3,2)
 
btn = Button (window, text = "nH",command=clicked,width=14,height=2)
placement002(0,2)
btn = Button (window, text = "uH",command=clicked,width=14,height=2)
placement002(1,2)
btn = Button (window, text = "mH",command=clicked,width=14,height=2)
placement002(2,2)
 
btn = Button (window, text = "pF",command=clicked,width=14,height=2)
placement002(0,5)
btn = Button (window, text = "nF",command=clicked,width=14,height=2)
placement002(1,5)
btn = Button (window, text = "uF",command=clicked,width=14,height=2)
placement002(2,5)
 
txt=Entry(window,width=7,font=("Arial Bold",16))#window001
placement003(0,0)
 
txt=Entry(window,width=7,font=("Arial Bold",16))#window002
placement003(1,0)
 
 
window.mainloop()