public function testFormatCode()
{
$object = new Axis();
$this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Axis', $object->setFormatCode());
$this->assertEquals('', $object->getFormatCode());
$this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Axis', $object->setFormatCode('AAAA'));
$this->assertEquals('AAAA', $object->getFormatCode());
}