package First;
my ($string1, $string2, @array1, @array2);
...
sub Function10 {
   $self = shift;

   $self->{string1}="here";#is this the correct way to set a class attribute
   $string2="there";#or is this? ... and what are the differences?
   @{$self->{array1}}=(1, 2, 3);#and what about this?
}
...