[issue4343] tkinter: add _get_master() and use it consistently

[Terry J. Reedy]

Terry J. Reedy added the comment:

The new function should be private. I closed #18131 as partially a duplicate of this.  It has a couple of other suggested wordings for the exception.

I consider the current behavior, in particular the failure of Variable and subclasses when the supposedly optional master is not passed, to be buggy.  So I think backporting should be considered when we settle on a patch.

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nosy: +serhiy.storchaka
title: New function in Tkinter.py: setup_master -> tkinter: add _get_master() and use it consistently

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<http://bugs.python.org/issue4343>
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