title: tkinter.tclError unknown option "-bd"
body: <p>I am started following an instructable link and there I'm doing an exercise in which I have to code a calculator in Tkinter. But I am facing an error.</p>
  
  <p>Here's the code:</p>
  
  <pre><code>from tkinter import *
  import tkinter
  import tkinter.messagebox
  from tkinter.ttk import Entry
  def process():
     try:
      number1=Entry.get(E1)
      number2=Entry.get(E2)
      operator=Entry.get(E3)
      number1=int(number1)
      number2=int(number2)
      if operator =="+":
         answer=number1+number2
      if operator =="-":
         answer=number1-number2
      if operator=="*":
         answer=number1*number2
      if operator=="/":
         answer=number1/number2
      Entry.insert(E4,0,answer)
      print(answer)
     except ValueError:
      tkinter.messagebox.showwarning("Warning","Please enter the value in integer")
  
  top = Tk()
  L1 = Label(top, text = "Physics")
  L1.place(x = 10,y = 10)
  E1 = Entry(top,bd=5)
  E1.grid(row=1,column=1)
  L2 = Label(top, text="Number 1",).grid(row=1,column=0)
  L3 = Label(top, text="Number 2",).grid(row=2,column=0)
  L4 = Label(top, text="Operator",).grid(row=3,column=0)
  L4 = Label(top, text="Answer",).grid(row=4,column=0)
  E2 = Entry(top,bd =5)
  E2.grid(row=2,column=1)
  E3 = Entry(top,bd =5)
  E3.grid(row=3,column=1)
  E4 = Entry(top,bd =5)
  E4.grid(row=4,column=1)
  B=Button(top, text ="Submit",command = process).grid(row=5,column=1,)
  
  top.mainloop()
  </code></pre>
  
  <p>Here's the full traceback:</p>
  
  <pre><code>File "f:/za/python/first.py", line 28, in &lt;module&gt;
  E1 = Entry(top,bd=5)
  File "D:\K.Hasan\Photos\New folder\lib\tkinter\ttk.py", line 669, in __init__
  Widget.__init__(self, master, widget or "ttk::entry", kw)
   File "D:\K.Hasan\Photos\New folder\lib\tkinter\ttk.py", line 557, in __init__
  tkinter.Widget.__init__(self, master, widgetname, kw=kw)
  File "D:\K.Hasan\Photos\New folder\lib\tkinter\__init__.py", line 2567, in __init__
  self.tk.call(
  _tkinter.TclError: unknown option "-bd"
  </code></pre>
  
  <p>any ideas?</p>
  
  <p>Can anyone pls solve the error?</p>
  
  <p>Thanks in advance.</p>