I could see a lots of question on adding woocommerce product attribute. But doing so, I could see those added attributes in this screen
wp-admin/edit.php?post_type=product&page=product_attributes
My question is how can we add the attributes via PHP code to so that it appears in this above specified woocommerce attribute screen ? My intention is to make these attributes visible under 'Layered Navs' widget to filter out.