How to clear/delete the contents of a Tkinter Text widget?

I am writing a Python program in TKinter on Ubuntu to import and print the name of files from particular folder in Text widget. It is just adding filenames to the previous filnames in the Text widget, but I want to clear it first, then add a fresh list of filenames. But I am struggling to clear the Text widget's previous list of filenames.

Can someone please explain how to clear a Text widget?

Screenshoot and coding is giving below:

import os
from Tkinter import *

def viewFile():
    path = os.path.expanduser("~/python")
    for f in os.listdir(path):
        tex.insert(END, f + "\n")

if __name__ == '__main__':
    root = Tk()

    step= root.attributes('-fullscreen', True)
    step = LabelFrame(root, text="FILE MANAGER", font="Arial 20 bold italic")
    step.grid(row=0, columnspan=7, sticky='W', padx=100, pady=5, ipadx=130, ipady=25)

    Button(step, text="File View", font="Arial 8 bold italic", activebackground=
           "turquoise", width=30, height=5, command=viewFile).grid(row=1, column=2)
    Button(step, text="Quit", font="Arial 8 bold italic", activebackground=
           "turquoise", width=20, height=5, command=root.quit).grid(row=1, column=5)

    tex = Text(master=root)
    scr=Scrollbar(root, orient=VERTICAL, command=tex.yview)
    scr.grid(row=2, column=2, rowspan=15, columnspan=1, sticky=NS)
    tex.grid(row=2, column=1, sticky=W)
    tex.config(yscrollcommand=scr.set, font=('Arial', 8, 'bold', 'italic'))

    root.mainloop()

I checked on my side by just adding '1.0' and it start working

tex.delete('1.0', END)

you can also try this