Fix the version number in which changes were made
diff --git a/Doc/lib/libtime.tex b/Doc/lib/libtime.tex
index f21f6a3..e315183 100644
--- a/Doc/lib/libtime.tex
+++ b/Doc/lib/libtime.tex
@@ -164,7 +164,7 @@
 Locale information is not used by \function{ctime()}.
 \versionchanged[Allowed \var{secs} to be omitted]{2.1}
 \versionchanged[If \var{secs} is \constant{None}, the current time is
-                used]{2.3}
+                used]{2.4}
 \end{funcdesc}
 
 \begin{datadesc}{daylight}
@@ -179,7 +179,7 @@
 above for a description of the \class{struct_time} object.
 \versionchanged[Allowed \var{secs} to be omitted]{2.1}
 \versionchanged[If \var{secs} is \constant{None}, the current time is
-                used]{2.3}
+                used]{2.4}
 \end{funcdesc}
 
 \begin{funcdesc}{localtime}{\optional{secs}}
@@ -189,7 +189,7 @@
 applies to the given time.
 \versionchanged[Allowed \var{secs} to be omitted]{2.1}
 \versionchanged[If \var{secs} is \constant{None}, the current time is
-                used]{2.3}
+                used]{2.4}
 \end{funcdesc}
 
 \begin{funcdesc}{mktime}{t}