public function testSetUnit()
 {
     $metric = new Metric();
     $this->tester->assertFalse($metric->setUnit('Invalid'), 'Metric::setUnit invalid unit set failed!');
     $metric->setUnit('Kilobits/Second');
     $this->tester->assertEquals('Kilobits/Second', $metric->getUnit(), 'Metric::setUnit failed!');
 }