How can I un-bind a button in Perl Tk

[ghosh123]

Hi Monk, I have the following PERL Tk code. Please tell me how can I un-bind the Button-1 ?

my $obj_A = A->new ; #creating object of A.pm

my $label = $frame->Label(-anchor =>'nw', -text => 'MyLabel");

$self->{labelName} = $label;

$label->bind("<Button-1>", 
              sub { $self->onEnter($label, $obj_A) ; }
            )

I want to un-bind the Button-1 so that it releases the $obj_A object and its ($obj_A) refcount reduces. Assume $self is object of B.pm. Can I do something like below ? Will it serve my purpose ?

$label->bind("<Button-1>", undef );