public function setForm(?string $form)
    {
        $this->form = $form;
        $this->_form = null !== $form;

        return $this;
    }
public function setForm(?string $form)
    {
        $this->form = $form;
        $this->_form = null !== $form;

        return $this;
    }
Set form

@param string $form
@return object