code: MomentInterval in(Timezone tz) {
  
          Boundary<Moment> b1;
          Boundary<Moment> b2;
  
          if (this.getStart().isInfinite()) {
              b1 = Boundary.infinitePast();
          } else {
              Moment m1 = this.getStart().getTemporal().in(tz);
              b1 = Boundary.of(this.getStart().getEdge(), m1);
          }
  
          if (this.getEnd().isInfinite()) {
              b2 = Boundary.infiniteFuture();
          } else {
              Moment m2 = this.getEnd().getTemporal().in(tz);
              b2 = Boundary.of(this.getEnd().getEdge(), m2);
          }
  
          return new MomentInterval(b1, b2);
  
      }
docs: combines this local timestamp interval with given timezone to a global UTC-interval