\expandafter\edef\csname :RestoreCatcodes\endcsname{%
\expandafter\ifx \csname :RestoreCatcodes\endcsname\relax\else
\csname :RestoreCatcodes\endcsname \fi
\catcode‘\noexpand :=\the\catcode‘:%
\let\expandafter\noexpand\csname :RestoreCatcodes\endcsname=
\noexpand\UnDefcS}
\catcode‘\:=11
-_-_-