code: public function get(string $key, $default = null)
      {
          $parts = explode('.', $key);
  
          $current = $this->data;
  
          while (count($parts) > 0) {
              $part = array_shift($parts);
  
              if (false === isset($current[$part])) {
                  return $default;
              }
  
              $current = $current[$part];
          }
  
          return $current;
      }
docs: @inheritdoc
  
  @param string $key
  @param mixed  $default
  
  @return mixed