my $TREELEVEL = [ [2], [1,2,3], [5,6,7]];

$self->ConfigSpecs
(
-treelevels         =>  ['METHOD',       qw/treelevels         Treelevels/,       $TREELEVEL/ ],
);

##</code><code>##

bad option "-treelevels": must be -after, -anchor, -before, -expand, -fill, -in, -ipadx, -ipady, -padx, -pady, or -side
at C:/PRG/Perl/site/lib/Tk/Widget.pm line 1214.