% brew install tcl-tk

% echo 'export PATH="/usr/local/opt/tcl-tk/bin:$PATH"' >> ~/.bash_profile
% export LDFLAGS="-L/usr/local/opt/tcl-tk/lib"
% export CPPFLAGS="-I/usr/local/opt/tcl-tk/include"
% export PKG_CONFIG_PATH="/usr/local/opt/tcl-tk/lib/pkgconfig"
% source ~/.bash_profile

% python -m tkinter

% python3
Python 3.9.0
>>>
>>> import tkinter
>>> tkinter._test()

>>> quit()

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