code: public function serialize(): string
  	{
  		return serialize([
  			'_type'         => $this->_type,
  			'_arrayOptions' => $this->_arrayOptions,
  			'_jsonOptions'  => $this->_jsonOptions,
  			'_container'    => $this->_container,
  		]);
  	}
docs: String representation of object.
  
  @link  https://php.net/manual/en/serializable.serialize.php
  @return string the string representation of the object or null