new_contents: 
  
  
  def merge_dict_sum(dict1, dict2):
      """
      Merge two dictionaries and add values of common keys.
      """
      dict3 = {**dict1, **dict2}
      for key, value in dict3.items():
          if key in dict1 and key in dict2:
              dict3[key] = value + dict1[key]
      return dict3
      
  def merge_dict_list(dict1, dict2):
      """
      Merge two dictionaries and add values of common keys.
      """
      dict3 = {**dict1, **dict2}
      for key, value in dict3.items():
          if key in dict1 and key in dict2:
              dict3[key] = [value, dict1[key]]
      return dict3
subject: Add methods in util