or download this
use SO;
my $so = SO->new('some.so');
...
my $x = { a => 'b', c => 123 };
my $r = $so->change_this_argument( $x );#get error from .so about wron
+g arguments, but the arguments definetly correct.
my $r2 = $so->accept_this_argument( $x );#get same error.