code: def hamming_calc(TP, POP):
      """
      Calculate Hamming loss.
  
      :param TP: true positive
      :type TP: dict
      :param POP: population or total number of samples
      :type POP: int
      :return: Hamming loss as float
      """
      try:
          length = POP
          return (1 / length) * (length - sum(TP.values()))
      except Exception:
          return "None"
  
imports: from __future__ import division
  import math
  import operator
  from functools import reduce
  from .pycm_interpret import *
  from .pycm_ci import kappa_SE_calc, CI_calc, SE_calc
  from .pycm_util import complement
label_desc: Use image node_id 19 for calling a global function with example usage: hamming_calc(TP, POP) and returns: unknown, str