code: private int getPhosphoProteinNodes(Collection<KamNode> nodes) {
          int count = 0;
          for (KamNode node : nodes) {
              if (node.getFunctionType() == FunctionEnum.PROTEIN_ABUNDANCE
                      && node.getLabel().indexOf("proteinModification(P") > -1) {
                  count++;
              }
          }
          return count;
      }
docs: return number of protein with phosphorylation modification
  @param nodes
  @return