Is there a way to detect a FocusOut event on 2 widgets in python
If I understand you correctly, you want the DateEntry not to be destroyed when you click open the calendar. That is doable by checking your current focus and pass if the current focus is a Calendar object.
import tkinter as tkfrom tkcalendar import DateEntry, Calendardef check_focus(event): current = root.focus_get() if not isinstance(current,Calendar): cal.destroy()root = tk.Tk()cal = DateEntry(root, year=2010)cal.pack(padx=10, pady=10)cal.bind('<FocusOut>', check_focus)tk.Button(root,text="Click").pack()root.mainloop()Try pressing tab to change focus and see.