public function set_fields()
{
$this->add_field(new acf_fields\text('Headline', 'headline', '1603242311a'));
$this->add_field(new acf_fields\textarea('Text', 'text', '1603242313a'));
$this->add_brick((new demo_button('button', '1603242312a'))->set_field_label_prefix('Button'));
}