[Tkinter] question for a tkinter dialog box

[RobertAlvarez424]

import tkinter as tk

root = tk.Tk()
logo = tk.PhotoImage(file="python_logo_small.gif")

w1 = tk.Label(root, image=logo).pack(side="right")

explanation = """At present, only GIF and PPM/PGM
formats are supported, but an interface 
exists to allow additional image file
formats to be added easily."""

w2 = tk.Label(root,
              justify=tk.LEFT,
              padx = 10,
              text=explanation).pack(side="left")
root.mainloop()

new to python and tkinter , here a sample code I got in this tutor for tkinter .

So between root = tk.Tk() and root.mainloop() is the code for this dialog box.
My question is w1 and w2 . These are defined but do not understand how they are called to be used in root.mainloop() ?

Yoriz write Aug-24-2021, 10:51 PM:
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