curl --location 'https://api.neucron.io/v1/asset21/balance?assetID=undefined' \
--header 'Content-Type: application/json' \
--data '[
"string"
]'[
{
"address": "1A1QNEkLuvAALsmG4Me3iubP8zb5C6jpv5",
"amt": 30300303,
"precised": 34.22
}
]