new section - builtin constants
diff --git a/Doc/lib/libconsts.tex b/Doc/lib/libconsts.tex
new file mode 100644
index 0000000..e8e620c
--- /dev/null
+++ b/Doc/lib/libconsts.tex
@@ -0,0 +1,20 @@
+\section{Builtin Constants}
+
+A small number of constants live in the builtin namespace. They are:
+
+\begin{datadesc}{False}
+The false value of the \code{bool} type.
+\versionadded{2.3}
+\end{datadesc}
+
+\begin{datadesc}{True}
+The true value of the \code{bool} type.
+\versionadded{2.3}
+\end{datadesc}
+
+\begin{datadesc}{None}
+The sole value of \code{NoneType}. \code{None} is frequently used to
+represent the absence of a value, as when default arguments are not passed
+to a function.
+\end{datadesc}
+