Como usar um evento virtual com o Tknter
import tkinter as tk
from tkinter import ttk
tkwindow = tk.Tk()
cbox = ttk.Combobox(tkwindow, values=[1,2,3], state='readonly')
cbox.grid(column=0, row=0)
cbox.bind("<<ComboboxSelected>>", lambda _ : print("Selected!"))
tkwindow.mainloop()
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