to_s:
size: 49
to_json:
first: pagegid://shopify/OnlineStorePage/125629693974
product.metafields.custom["size"] =>
product.metafields.custom.size => 49

product.metafields.custom["first"] =>
product.metafields.custom.first => pagegid://shopify/OnlineStorePage/125629693974

product.metafields.custom["last"] =>
product.metafields.custom.last =>

product.metafields.custom["to_h"] =>
product.metafields.custom.to_h =>

product.metafields.custom["to_liquid"] =>
product.metafields.custom.to_liquid =>