code: func (b *Blob) StaticSetMembers() []blob.Ref {
  	if b.Type() != "static-set" {
  		return nil
  	}
  
  	s := make([]blob.Ref, 0, len(b.ss.Members))
  	for _, ref := range b.ss.Members {
  		if ref.Valid() {
  			s = append(s, ref)
  		}
  	}
  	return s
  }
docs: // StaticSetMembers returns the refs in the "members" field if b is a valid
  // "static-set" schema. Note that if it is a large static-set, the members are
  // actually spread as subsets in "mergeSets". See StaticSetMergeSets.