public static function get_attributes( $field, $value = null ) {
$attributes = wp_parse_args( $field['attributes'], array(
'disabled' => $field['disabled'],
'required' => $field['required'],
'id' => $field['id'],
'class' => '',
'name' => $field['field_name'],
) );
$attributes['class'] = implode( ' ', array_merge( array( "rwmb-{$field['type']}" ), (array) $attributes['class'] ) );
return $attributes;
}