code: def post_build_time_coverage(self):
          
          from ambry.util.datestimes import expand_to_years
  
          years = set()
  
          # From the bundle about
          if self.metadata.about.time:
              for year in expand_to_years(self.metadata.about.time):
                  years.add(year)
  
          # From the bundle name
          if self.identity.btime:
              for year in expand_to_years(self.identity.btime):
                  years.add(year)
  
          # From all of the partitions
          for p in self.partitions:
              years |= set(p.time_coverage)
docs: Collect all of the time coverage for the bundle.