const golang.org/x/text/language._ZZ

2 uses

	golang.org/x/text/language (current package)
		language.go#L317: 	return Region{_ZZ}, No // TODO: return world instead of undetermined?
		tables.go#L32: 	_ZZ  = 358

The pages are generated with Golds v0.7.6. (GOOS=linux GOARCH=amd64)