$np->{'player_b'} = $pos->{'player_b'};
my ($move, $nb) = $pos->{'board'}->prettyprint_move($from_row, $from_col, $to_row, $to_col, $promo);
$np->{'last_move'} = $move;
$np->{'player_b'} = $pos->{'player_b'};
my ($move, $nb) = $pos->{'board'}->prettyprint_move($from_row, $from_col, $to_row, $to_col, $promo);
$np->{'last_move'} = $move;