years property
get all years that overlap with a the Timespan
Implementation
Iterable<Timespan> get years sync* {
DateTime i = begin.beginOfYear();
int counter = 0;
do {
yield Timespan(
begin: DateTime(i.year + counter),
end: DateTime(i.year + counter + 1).subtract(const Duration(hours: 1)));
counter++;
} while (DateTime(begin.year + counter).isBefore(end));
}