Make a group be admincc of one ticket by scrip

I have a scrip that uses the following custom action. This code means that add a constant user by email address "" to the admincc list of one ticket:

my $admincclist = $self->TicketObj->AdminCc;
my $user = RT::User->new($RT::SystemUser);


I want to set a group be admincc instead of one user. how can I do it?