DNEnvironment::onAfterWrite PHP Method

    public function onAfterWrite()
    {
        parent::onAfterWrite();
        if ($this->Usage === self::PRODUCTION || $this->Usage === self::UAT) {
            $conflicting = DNEnvironment::get()->filter('ProjectID', $this->ProjectID)->filter('Usage', $this->Usage)->exclude('ID', $this->ID);
            foreach ($conflicting as $otherEnvironment) {
                $otherEnvironment->Usage = self::UNSPECIFIED;
                $otherEnvironment->write();
            }
        }
    }