public function mergeFrom(PhoneNumber $other)
    {
        if ($other->hasCountryCode()) {
            $this->setCountryCode($other->getCountryCode());
        }
        if ($other->hasNationalNumber()) {
            $this->setNationalNumber($other->getNationalNumber());
        }
        if ($other->hasExtension()) {
            $this->setExtension($other->getExtension());
        }
        if ($other->hasItalianLeadingZero()) {
            $this->setItalianLeadingZero($other->isItalianLeadingZero());
        }
        if ($other->hasNumberOfLeadingZeros()) {
            $this->setNumberOfLeadingZeros($other->getNumberOfLeadingZeros());
        }
        if ($other->hasRawInput()) {
            $this->setRawInput($other->getRawInput());
        }
        if ($other->hasCountryCodeSource()) {
            $this->setCountryCodeSource($other->getCountryCodeSource());
        }
        if ($other->hasPreferredDomesticCarrierCode()) {
            $this->setPreferredDomesticCarrierCode($other->getPreferredDomesticCarrierCode());
        }
        return $this;
    }