curl --location --request POST 'https://demo.myshopify.com//admin/api//custom_collections.json'
{
"custom_collection": {
"id": 1063001333,
"handle": "ipods-1",
"title": "IPods",
"updated_at": "2023-01-03T13:04:13-05:00",
"body_html": null,
"published_at": "2023-01-03T13:04:13-05:00",
"sort_order": "best-selling",
"template_suffix": null,
"published_scope": "web",
"admin_graphql_api_id": "gid://shopify/Collection/1063001333"
}
}