footnote about nested ifs

book.tex

@@ -22,7 +22,7 @@
 
 \def\racketEd{0}
 \def\pythonEd{1}
-\def\edition{0}
+\def\edition{1}
 
 % material that is specific to the Racket edition of the book
 \newcommand{\racket}[1]{{\if\edition\racketEd\color{olive}{#1}\fi}}
@@ -7422,7 +7422,13 @@ can be an arbitrary expression in \LangIf{} whereas in \LangCIf{} the
 condition must be a comparison.
 
 As a motivating example, consider the following program that has an
-\key{if} expression nested in the condition of another \key{if}.
+\key{if} expression nested in the condition of another \key{if}.%
+\python{\footnote{Programmers rarely write nested \code{if}
+  expressions, but it is not uncommon for the condition of an
+  \code{if} statement to be a call of a function that also contains an
+  \code{if} statement.  When such a function is inlined, the result is
+  a nested \code{if} that requires the techniques discussed in this
+  section.}}
 % cond_test_41.rkt, if_lt_eq.py
 \begin{center}
 \begin{minipage}{0.96\textwidth}