code: public static PipelineOptions tweakOptions(PipelineOptions opts) {
      if (!DataflowRunner.class.isAssignableFrom(opts.getRunner())) {
        return opts;
      }
      DataflowPipelineOptions dataflowOpts = opts.as(DataflowPipelineOptions.class);
  
      // By default, dataflow allocates 250 GB local disks, thats not necessary. Lower it unless the
      // user requested an explicit size
      if (dataflowOpts.getDiskSizeGb() == 0) {
        dataflowOpts.setDiskSizeGb(25);
      }
  
      return dataflowOpts;
    }
docs: Helper to tweak default pipelineOptions for import/export jobs
  @param opts
  @return PipelineOptions