code: def sum_dicts(dicts, normalize=False):
      
      sum_dict = {}
      for dicti in dicts:
          for key in dicti:
              val = dicti[key]
              if isinstance(val, numbers.Number):
                  sum_dict[key] = sum_dict.get(key, 0) + val
              else:
                  sum_dict[key] = val
      if normalize:
          return norm_int_dict(sum_dict)
      return sum_dict
docs: Sums the given dicts into a single dict mapping each numberic-valued
      key to the sum of its mappings in all given dicts. Keys mapping to
      non-numeric values retain the last value (by the given order).
  
      Parameters
      ----------
      dicts : list
          A list of dict objects mapping each key to an numeric value.
      normalize : bool, default False
          Indicated whether to normalize all values by value sum.
  
      Returns
      -------
      dict
          A dict where each key is mapped to the sum of its mappings in all
          given dicts.