A post town is not the same as a locality. A post town can encompass a collection of (small) localities. It can also be a subpart of a locality. An actual post town in Norway is "Bergen".
Number of the Mail stop. eg. 123 in MS 123
PostalCode is the container element for either simple or complex (extended) postal codes. Type: Area Code, Postcode, etc.
Used by postal services to encode the name of the element.
eg. village, town, suburb, etc
Name of the the Mail Stop. eg. MSP, MS, etc
A MailStop is where the the mail is delivered to within a premise/subpremise/firm or a facility.
Specification of a firm, company, organization, etc. It can be specified as part of an address that contains a street or a postbox. It is therefore different from
a large mail user address, which contains no street.