code: func (c *InstanceCache) getAccessTime(ctx context.Context, now time.Time, pin common.Pin) (lastAccess time.Time, ok bool) {
  	c.withState(ctx, now, func(s *messages.InstanceCache) {
  		var entry *messages.InstanceCache_Entry
  		if entry, ok = s.Entries[pin.InstanceID]; ok {
  			lastAccess = google.TimeFromProto(entry.LastAccess)
  		}
  	})
  	return
  }
docs: // getAccessTime returns last access time of an instance.
  // Used for testing.