\item The \method{sort()} method of lists gained three keyword

arguments, \var{cmp}, \var{key}, and \var{reverse}. These arguments

make some common usages of \method{sort()} simpler. All are optional.

\var{cmp} is the same as the previous single argument to

\method{sort()}; if provided, the value should be a comparison

function that takes two arguments and returns -1, 0, or +1 depending

on how the arguments compare.

\var{key} should be a single-argument function that takes a list

element and returns a comparison key for the element. The list is

then sorted using the comparison keys. The following example sorts a list

case-insensitively:

\begin{verbatim}

\end{verbatim}

The last example, which uses the \var{cmp} parameter, is the old way

to perform a case-insensitive sort. It works, but is slower than

using a \var{key} parameter. Using \var{key} results in calling the

\method{lower()} method once for each element in the list while using

\var{cmp} will call the method twice for each comparison.

The \var{reverse} parameter should have a Boolean value. If the value is

\constant{True}, the list will be sorted into reverse order. Instead

of \code{L.sort() ; L.reverse()}, you can now write

\code{L.sort(reverse=True)}.