code: public function post($endpoint, $data, $query = [])
      {
          $endpoint = $this->buildUri($endpoint, $query);
          $headers = $this->buildHeaders();
          $data = $this->prepareData($data);
  
          $this->response = $this->client->post($endpoint, $data, $headers);
  
          return $this->response;
      }
docs: POST request.
  
  @param string       $endpoint The sub endpoint
  @param string|array $data     The data to be submited
  @param array        $query    Query parameters
  
  @return object