sub write_header {
use strict;
use Text::Template;
my $rvars = shift;
my %vars = %$rvars;
# get time
my $now_string = localtime;
$vars{"date"} = $now_string;
my $header = $vars{"header"};
my $template2 = Text::Template->new(SOURCE => $header)
          or die "Couldn't construct template: $!";
my $result2 = $template2->fill_in(HASH => \%vars);
return \$result2;
}