sub init {
  my $self = shift;
  my $args = shift;
  unlock_keys( %{ $self } );

  # $self->SUPER::init( $args );  # uncomment if this is a child class

  # define new attributes
  my $attributes = {
           ### fill-in name/value pairs of attributes here
           # name            => $args->{ name },
             attribute       => $args->{ attribute },
             objectdata      => $args->{ objectdata } || 23,
             parameter       => $args->{ parameter } || 'bupkes',
           };

  # add attributes to object
  my @fields = (keys %{ $attributes });
  @{ $self }{ @fields } = @{ $attributes }{ @fields };    # hash slice

  lock_keys( %{ $self } );
  return $self;
}