Should I use from tkinter import * or import tkinter as tk?

I have a script I'm writing, and I start like this:

from tkinter import *
import tkinter.messagebox as mbx
import tkinter.filedialog as fd
root = Tk()

Should I use

import tkinter as tk`
x = tk.Text(root)

or use

from tkinter import *
x = Text(root)

as I always used to do?