Use option wrap=WORD. Here is an example:
from tkinter import *
root = Tk()
t = Text(wrap=WORD)
t.pack()
root.mainloop()
Alternatively, you can set the value for wrapwith Text.config():
t = Text()
t.config(wrap=WORD)
Other valid values for wrapare CHAR, which is the default value, or NONE, in which case the wrap does not occur, and the line will grow indefinitely.
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