The mapping file is simply a pain text file, where the placeholders (patters) to be used within the template are defined. Unlike the template file, the placeholders within the mapping file should not contain angled brackets. Each placeholder should be on a separate line, e.g.
company_address
company_contact
Comments can also be included within the mapping file, each
line starting with a '#' character are considered to be comments
and are ignored when parsing the file.