like this similar example but not working. it checks for cookies with value and modify it automatically. every time when u execute the script. it modify the cookie with new specified value

#!/usr/bin/perl 

use CGI::Cookie;


my %cookies = fetch CGI::Cookie;
my $new_value = 'modify';

print "Content-type: text/html\n\n";
foreach (keys %cookies) {
   #change value of NewCookie
    if($_ eq 'NewCookie')   {
        my $val_cookie = $cookies{'NewCookie'}->value;
        print "\n value of NewCookie =>" . $val_cookie;
       $cookies{'NewCookie'}->value($new_value);
       $cookies{'NewCookie'}->bake;
    }
}
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