List every currency and asset we quote

{
  "object": "list",
  "data": [
    {
      "object": "currency",
      "code": "GBP",
      "type": "fiat"
    },
    {
      "object": "currency",
      "code": "NGN",
      "type": "fiat"
    },
    {
      "object": "currency",
      "code": "USDT",
      "type": "crypto"
    }
  ],
  "next_cursor": null,
  "has_more": false
}