{
       local $" = "\n";
       open my $fh, '>', "$ENV{HOME}/number_list.txt"
           or die $!;
       print $fh "@list\n";
   }

##</code><code>##

   my $prefix = "something";
   {
       local $" = "\n$prefix";
       open my $fh, '>', "$ENV{HOME}/number_list.txt"
           or die $!;
       print $fh "$prefix@list\n";
   }