Perfil del emisor GET

using var http = new HttpClient();
http.DefaultRequestHeaders.Add("X-Api-Key", apiKey);
string json = await http.GetStringAsync(
    "https://staging-api.mynexusapi.com/v1/contribuyentes/0123456789001/perfil");

import os, requests

r = requests.get(
    "https://staging-api.mynexusapi.com/v1/contribuyentes/0123456789001/perfil",
    headers={"X-Api-Key": os.environ["ECUAFACT_API_KEY"]},
    timeout=30)
print(r.json())

const res = await fetch(
  "https://staging-api.mynexusapi.com/v1/contribuyentes/0123456789001/perfil",
  { headers: { "X-Api-Key": process.env.ECUAFACT_API_KEY } });
console.log(await res.json());

<?php
$ch = curl_init("https://staging-api.mynexusapi.com/v1/contribuyentes/0123456789001/perfil");
curl_setopt_array($ch, [
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_HTTPHEADER => ["X-Api-Key: " . getenv("ECUAFACT_API_KEY")],
]);
echo curl_exec($ch);
curl_close($ch);

import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;

HttpClient cliente = HttpClient.newHttpClient();
HttpRequest peticion = HttpRequest.newBuilder()
    .uri(URI.create("https://staging-api.mynexusapi.com/v1/contribuyentes/0123456789001/perfil"))
    .header("X-Api-Key", System.getenv("ECUAFACT_API_KEY"))
    .GET()
    .build();
HttpResponse<String> respuesta = cliente.send(peticion, HttpResponse.BodyHandlers.ofString());
System.out.println(respuesta.body());