func (m *OuiDb) VendorLookup(s string) (string, error) {
	addr, err := net.ParseMAC(s)
	if err != nil {
		return "", err
	}
	block := m.Lookup(HardwareAddr(addr))
	if block == nil {
		return "", ErrInvalidMACAddress
	}
	return block.Organization, nil
}
func (m *OuiDb) VendorLookup(s string) (string, error) {
	addr, err := net.ParseMAC(s)
	if err != nil {
		return "", err
	}
	block := m.Lookup(HardwareAddr(addr))
	if block == nil {
		return "", ErrInvalidMACAddress
	}
	return block.Organization, nil
}
// VendorLookup obtains the vendor organization name from the MAC address s.