\documentclass[]{article}
\usepackage{testadr}
\begin{document}

\setdefs

\typeout{Making conversions}

\setadrto{\adrSUb} 

\setadrfr{\adrPJb}

This one does what I want to do, but doesn't work.

aaaaaaaaaaaaaaaaaa

From:

\listfr

bbbbbbbbbbbbbbbbbb

To: 

\listto

cccccccccccccccccc
\end{document}

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