\newcount\fs
\def\sz#1#2{\fs=#1#2
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 \else\ifnum\fs=12\fontsize{12}{18pt plus1pt minus .8pt}\selectfont
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 \else\ifnum\fs=25\fontsize{24.88}{33pt plus1.5pt minus 1pt}\selectfont
 \fi\fi\fi\fi\fi\fi\fi}


