if a null value is passed to the constructor a Fatal error is thrown. `PHP Fatal error: Uncaught TypeError: UkPostcode::__construct(): Argument #1 ($postcode) must be of type string, null given, called in`
if a null value is passed to the constructor a Fatal error is thrown.
PHP Fatal error: Uncaught TypeError: UkPostcode::__construct(): Argument #1 ($postcode) must be of type string, null given, called in