Template:Television series set in year category/doc

Creates a category of the form "Television series set in YYYY", where YYYY is a 4-digit year.

e.g.
 * Category:Television series set in 1977 ✅
 * Category:Television series set in 2020 ✅

It is not for use on other categories, e.g.
 * Category:Television series set in the 1990s ❌

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 "Television series set in YYYY"