curl --request POST \
  --url https://arc-mainnet.core.chainstack.com/mt_c524ad9781ae5dccd9ac6f5b0370e/ \
  --header 'Content-Type: application/json' \
  --data '
{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "eth_getHeaderByNumber",
  "params": [
    "0x1c69aef"
  ]
}
'

import requests

url = "https://arc-mainnet.core.chainstack.com/mt_c524ad9781ae5dccd9ac6f5b0370e/"

payload = {
    "id": 1,
    "jsonrpc": "2.0",
    "method": "eth_getHeaderByNumber",
    "params": ["0x1c69aef"]
}
headers = {"Content-Type": "application/json"}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {'Content-Type': 'application/json'},
  body: JSON.stringify({id: 1, jsonrpc: '2.0', method: 'eth_getHeaderByNumber', params: ['0x1c69aef']})
};

fetch('https://arc-mainnet.core.chainstack.com/mt_c524ad9781ae5dccd9ac6f5b0370e/', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://arc-mainnet.core.chainstack.com/mt_c524ad9781ae5dccd9ac6f5b0370e/",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'id' => 1,
    'jsonrpc' => '2.0',
    'method' => 'eth_getHeaderByNumber',
    'params' => [
        '0x1c69aef'
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://arc-mainnet.core.chainstack.com/mt_c524ad9781ae5dccd9ac6f5b0370e/"

	payload := strings.NewReader("{\n  \"id\": 1,\n  \"jsonrpc\": \"2.0\",\n  \"method\": \"eth_getHeaderByNumber\",\n  \"params\": [\n    \"0x1c69aef\"\n  ]\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://arc-mainnet.core.chainstack.com/mt_c524ad9781ae5dccd9ac6f5b0370e/")
  .header("Content-Type", "application/json")
  .body("{\n  \"id\": 1,\n  \"jsonrpc\": \"2.0\",\n  \"method\": \"eth_getHeaderByNumber\",\n  \"params\": [\n    \"0x1c69aef\"\n  ]\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://arc-mainnet.core.chainstack.com/mt_c524ad9781ae5dccd9ac6f5b0370e/")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["Content-Type"] = 'application/json'
request.body = "{\n  \"id\": 1,\n  \"jsonrpc\": \"2.0\",\n  \"method\": \"eth_getHeaderByNumber\",\n  \"params\": [\n    \"0x1c69aef\"\n  ]\n}"

response = http.request(request)
puts response.read_body

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "hash": "0xb27e862c03e649114afd6904bd39f5e4a1ca41fffb92c0bbfe88dd7750b8c9a1",
    "parentHash": "0xd2a71aa35723f197449b661b47cf6c0aaedb562ae1da08c6f5067ea4095ee79f",
    "sha3Uncles": "0x1dcc4de8dec75d7aab85b567b6ccd41ad312451b948a7413f0a142fd40d49347",
    "miner": "0x00daa83172e09404e9e37974a8e9380921395d8c",
    "stateRoot": "0x977b3441f570da3e0a72c9ad16298fe3d448cba356f9f25bff34f1d63fb0ab66",
    "transactionsRoot": "0x78fae8c0f384f9df5dfbf3ac0dea23ac1055f3129bb1470c1cc2d7674793f8f6",
    "receiptsRoot": "0xefcfc6fe1dd737dd5fbaa47c1cca728ca4cc33f0917813c7e3306e90a8f670a4",
    "logsBloom": "0x00000000000000800000000000000000000000000000000000000004000000000000000000000200000000000000000000000000000020001000000000000000000000000000000800002018000000000100000000000000000000000000000000000000000000002040100010002000000000000000000000000010000800400000000000000000000000000000000000000000000002000010000000010000000000000000000000000000000100000000000000000000000000000000004000000002000000000008000000000082000000800010000400000000000000400000000000000000000000000000000000000000008000000000000000000000",
    "difficulty": "0x0",
    "number": "0x1c69aef",
    "gasLimit": "0x1c9c380",
    "gasUsed": "0x29be9",
    "timestamp": "0x6aed6f00",
    "extraData": "0x00000004a817c800",
    "mixHash": "0x0000000000000000000000000000000000000000000000000000000000000000",
    "nonce": "0x0000000000000000",
    "baseFeePerGas": "0x4a817c800",
    "withdrawalsRoot": "0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421",
    "blobGasUsed": "0x0",
    "excessBlobGas": "0x0",
    "parentBeaconBlockRoot": "0xd2a71aa35723f197449b661b47cf6c0aaedb562ae1da08c6f5067ea4095ee79f",
    "requestsHash": "0xe3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
    "size": "0x3f8"
  }
}