Fix markup error
diff --git a/Doc/whatsnew/whatsnew20.tex b/Doc/whatsnew/whatsnew20.tex
index d3ffcdb..9f742c7 100644
--- a/Doc/whatsnew/whatsnew20.tex
+++ b/Doc/whatsnew/whatsnew20.tex
@@ -280,7 +280,7 @@
The full list of supported assignment operators is \code{+=},
\code{-=}, \code{*=}, \code{/=}, \code{\%=}, \code{**=}, \code{\&=},
-\code{|=}, \code{^=}, \code{>>=}, and \code{<<=}. Python classes can
+\code{|=}, \verb|^=|, \code{>>=}, and \code{<<=}. Python classes can
override the augmented assignment operators by defining methods named
\method{__iadd__}, \method{__isub__}, etc. For example, the following
\class{Number} class stores a number and supports using += to create a