curl --request POST \
  --url https://rpc.quai.network/cyprus1/ \
  --header 'Content-Type: application/json' \
  --data '
{
  "jsonrpc": "2.0",
  "method": "quai_getHeaderHashByNumber",
  "params": [
    "0x15d"
  ],
  "id": 1
}
'

{
  "jsonrpc": "2.0",
  "result": "0x0000024ccfb37a6e7ba09a3541c6c1e614e64809cc1b742acad2451e22764d6c",
  "id": 1
}