Add a comment showing how one of the macros should be used.

Doc/texinputs/python.sty

@@ -804,6 +804,7 @@
 \newcommand{\NULL}{\constant{NULL}}
 \newcommand{\infinity}{\ensuremath{\infty}}
 \newcommand{\plusminus}{\ensuremath{\pm}}
+% \menuselection{Start \sub Programs \sub Python}
 \newcommand{\menuselection}[1]{{\def\sub{ \ensuremath{>} }#1}}
 
 % Also for consistency: spell Python "Python", not "python"!