Template:Decade nationality television series debuts or endings category/doc

Creates a category of the form "YYY0s nationality television series debuts" or "YYY0s nationality television series endings", where YYY0s is a 4-digit decade and nationality is a valid nationality.

The template detects whether it is being used on a "debuts" or "endings" category, and adjusts its output to suit.

e.g.
 * Category:1970s Danish television series debuts ✅
 * Category:2020s Chinese television series endings ✅

It is not for use on other types of category, e.g.
 * Category:1957 American television series debuts ❌
 * Category:1969 American television series endings ❌

Usage
No parameters needed

Errors
If the template is used on an invalid page, an error message is generated and the page is categorised in:
 * Category: (population: )

Errors include:


 * The page is not in the category namespace
 * The page's title does not take the form "YYY0s nationality television series debuts" or "YYY0s nationality television series endings"
 * The value of "nationality" does not correspond to a country name.  The conversion is made using, so the problem may be a glitch in that template's lookup table