curl --request POST \
  --url https://{workspace}.spreesuite.com/billspree/users/make-users \
  --header 'Authorization: <api-key>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "users": [
    {
      "country": "US",
      "name": "Jane Doe",
      "email": "jane@example.com",
      "contacts": [
        {
          "contactType": "Mobile",
          "contactValue": "555-0100"
        }
      ]
    }
  ],
  "userType": "customer",
  "method": "Create",
  "action": "Create Parties",
  "apiVersion": "v2"
}
'

import requests

url = "https://{workspace}.spreesuite.com/billspree/users/make-users"

payload = {
    "users": [
        {
            "country": "US",
            "name": "Jane Doe",
            "email": "jane@example.com",
            "contacts": [
                {
                    "contactType": "Mobile",
                    "contactValue": "555-0100"
                }
            ]
        }
    ],
    "userType": "customer",
    "method": "Create",
    "action": "Create Parties",
    "apiVersion": "v2"
}
headers = {
    "Authorization": "<api-key>",
    "Content-Type": "application/json"
}

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

print(response.text)

const options = {
  method: 'POST',
  headers: {Authorization: '<api-key>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    users: [
      {
        country: 'US',
        name: 'Jane Doe',
        email: 'jane@example.com',
        contacts: [{contactType: 'Mobile', contactValue: '555-0100'}]
      }
    ],
    userType: 'customer',
    method: 'Create',
    action: 'Create Parties',
    apiVersion: 'v2'
  })
};

fetch('https://{workspace}.spreesuite.com/billspree/users/make-users', 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://{workspace}.spreesuite.com/billspree/users/make-users",
  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([
    'users' => [
        [
                'country' => 'US',
                'name' => 'Jane Doe',
                'email' => 'jane@example.com',
                'contacts' => [
                                [
                                                                'contactType' => 'Mobile',
                                                                'contactValue' => '555-0100'
                                ]
                ]
        ]
    ],
    'userType' => 'customer',
    'method' => 'Create',
    'action' => 'Create Parties',
    'apiVersion' => 'v2'
  ]),
  CURLOPT_HTTPHEADER => [
    "Authorization: <api-key>",
    "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://{workspace}.spreesuite.com/billspree/users/make-users"

	payload := strings.NewReader("{\n  \"users\": [\n    {\n      \"country\": \"US\",\n      \"name\": \"Jane Doe\",\n      \"email\": \"jane@example.com\",\n      \"contacts\": [\n        {\n          \"contactType\": \"Mobile\",\n          \"contactValue\": \"555-0100\"\n        }\n      ]\n    }\n  ],\n  \"userType\": \"customer\",\n  \"method\": \"Create\",\n  \"action\": \"Create Parties\",\n  \"apiVersion\": \"v2\"\n}")

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

	req.Header.Add("Authorization", "<api-key>")
	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://{workspace}.spreesuite.com/billspree/users/make-users")
  .header("Authorization", "<api-key>")
  .header("Content-Type", "application/json")
  .body("{\n  \"users\": [\n    {\n      \"country\": \"US\",\n      \"name\": \"Jane Doe\",\n      \"email\": \"jane@example.com\",\n      \"contacts\": [\n        {\n          \"contactType\": \"Mobile\",\n          \"contactValue\": \"555-0100\"\n        }\n      ]\n    }\n  ],\n  \"userType\": \"customer\",\n  \"method\": \"Create\",\n  \"action\": \"Create Parties\",\n  \"apiVersion\": \"v2\"\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://{workspace}.spreesuite.com/billspree/users/make-users")

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

request = Net::HTTP::Post.new(url)
request["Authorization"] = '<api-key>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"users\": [\n    {\n      \"country\": \"US\",\n      \"name\": \"Jane Doe\",\n      \"email\": \"jane@example.com\",\n      \"contacts\": [\n        {\n          \"contactType\": \"Mobile\",\n          \"contactValue\": \"555-0100\"\n        }\n      ]\n    }\n  ],\n  \"userType\": \"customer\",\n  \"method\": \"Create\",\n  \"action\": \"Create Parties\",\n  \"apiVersion\": \"v2\"\n}"

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

{
  "success": true,
  "statusCode": 200,
  "message": "Request Succeeded.",
  "error": null,
  "data": {}
}