new_contents: def gen_composite_processor(*funcs):
      """Applies the each func on the metrics in a chain"""
  
      def composite_processor(host, name, val, timestamp):
          tmp = host, name, val, timestamp
          for func in funcs:
              tmp = func(*tmp)
              if tmp is None:
                  break
          return tmp
      return composite_processor
  
subject: Add function to create composite processors