my @rules = (
  AM_Key => sub { push @{$_[4]->{pad}{am_keys}}, $_[1]{_content}; return },
  LK_Key => sub { push @{$_[4]->{pad}{lk_keys}}, $_[1]{_content}; return },
  Outpatient_Services => sub { LK_Keys => $_[4]->{pad}{lk_keys}, AM_Keys => $_[4]->{pad}{am_keys}},
  _default => undef,
);
my $xr = XML::Rules->new( rules => \@rules );