pack_tkINTER

#!/usr/bin/env python
# -*- coding: utf-8 -*-
#
# posicionamiento pack

import tkinter as tk
from tkinter import ttk

ventana = tk.Tk()
ventana.title("Posicionamiento grid")
ventana.config(bg="Light Steel Blue")

entry = ttk.Entry()
entry.pack(side=tk.LEFT)

boton = ttk.Button(text="Hola")
boton.pack(padx=30, pady=50, ipadx=10, ipady=20, expand=True, fill=tk.BOTH)


entry = ttk.Entry()
entry.pack()

ventana.mainloop()