filedialog file vs filename

So far we have been using the `tkinter.filedialog.askopenfilename` and `tkinter.filedialog.asksaveasfilename` functions to obtain the location of the files to be opened and saved. Should we instead use the `tkinter.filedialog.askopenfile(mode='r', **options)` and `tkinter.filedialog.asksaveasfile(mode='w', **options)` to return the file objects instead? Would this allow us to reduce the amount of code in that we would separately not have to open the files?

Start by inspecting the current uses of tkinter.filedialog.askopenfilename and asksaveasfilename, then compare them with askopenfile(mode='r', **options) and asksaveasfile(mode='w', **options). Determine whether returning file objects can remove separate file-opening code without changing the editor's open and save behavior; the issue is done when that approach and its scope are resolved.

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