code: public function postRequest($path, $options, $addApiKey)
      {
          if (isset($options['source']) && is_array($options['source'])) {
              $sources = $options['source'];
              unset($options['source']);
              foreach ($sources as $i => $source) {
                  $options["source[$i]"] = $source;
              }
          }
  
          $response = $this->makeRequest('POST', $path, $options, $addApiKey);
          return $this->parseResponse($response);
      }
docs: Make a POST request to the given endpoint and return the response
  
  @param string $path      the path to call on
  @param array  $options   the options to call with
  @param bool   $addApiKey whether or not to add the api key
  
  @return array the response object (parsed)