def last_bookmark(bookmarks):
last = None<EOL>for bookmark in bookmarks:<EOL><INDENT>if last is None:<EOL><INDENT>last = bookmark<EOL><DEDENT>else:<EOL><INDENT>last = _last_bookmark(last, bookmark)<EOL><DEDENT><DEDENT>return last<EOL>
The bookmark returned by the last :class:`.Transaction`.