PHP cURL Request/Response JSON

Debugging an integrators code that was written in PHP and came up with this test snippet.  I'm using php cURL as it is the simplest to convert and compare with the command line interface of cURL

<?php

$curl = curl_init();

curl_setopt_array($curl, array(
  CURLOPT_URL => 'https://<test_url_here>',
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => '',
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 0,
  CURLOPT_FOLLOWLOCATION => true,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => 'POST',
  CURLOPT_POSTFIELDS =>'{
  "email_addresses": [
    {
      "address": "test@tester.com",
      "is_default": true,
      "type": "home"
    }
  ],
  "first_name": "new first first_name",
  "last_name": "new last name",
  "phones": [
    {
      "extension": "1",
      "is_default": true,
      "number": "123456789",
      "type": "home"
    }
  ]
}',
  CURLOPT_HTTPHEADER => array(
    'User-Agent: Happy Times',
    'Authorization: Basic <auth_token_here>',
    'Content-Type: application/json'
  ),
));

$response = curl_exec($curl);

curl_close($curl);
echo $response;