\end{methoddesc}
\begin{methoddesc}[string]{partition}{sep}
-Splits the string at the \var{sep}, and return a 3-tuple containing
-the part before the separator, the separator itself, and the part
-after the separator. If the separator is not found, return a 3-tuple
-containing the string itself, followed by two empty strings.
+Splits the string at the first occurence of \var{sep}, and return
+a 3-tuple containing the part before the separator, the separator
+itself, and the part after the separator. If the separator is not
+found, return a 3-tuple containing the string itself, followed by
+two empty strings.
\versionadded{2.5}
\end{methoddesc}