docs: protected MultilabelInstancesHeader generateMultilabelHeader(Instances si) {
          Instances mi = new Instances(si, 0, 0);
          mi.setClassIndex(-1);
          mi.deleteAttributeAt(mi.numAttributes() - 1);
          FastVector bfv = new FastVector();
          bfv.addElement("0");
          bfv.addElement("1");
          for (int i = 0; i < this.m_L; i++) {
              mi.insertAttributeAt(new Attribute("class" + i, bfv), i);
          }
          this.multilabelStreamTemplate = mi;
          this.multilabelStreamTemplate.setRelationName("SYN_Z" + this.labelCardinalityOption.getValue() + "L" + this.m_L + "X" + m_A + "S" + metaRandomSeedOption.getValue() + ": -C " + this.m_L);
          this.multilabelStreamTemplate.setClassIndex(this.m_L);
          return new MultilabelInstancesHeader(multilabelStreamTemplate, m_L);
      }