human
Solve the following python programming problem given the following code:
def _CombineResults(result_list, combine_histograms = True) : 
    'Combine results from multiple YCSB clients.

  Reduces a list of YCSB results (the output of ParseResults)
  into a single result. Histogram bin counts, operation counts, and throughput
  are summed.
RunTime is replaced by the maximum runtime of any result.

  Args:
    result_list: List of ParseResults outputs.
    combine_histograms: If true, histogram bins are summed across results. If
      not, no histogram will be returned. Defaults to True.
  Returns:
    A dictionary, as returned by ParseResults.
  ' 
    def DropUnaggregated(result) : 
        "Remove statistics which 'operators' specify should not be combined." 
        drop_keys = { k for (k, v) in AGGREGATE_OPERATORS.iteritems () if (v is None) } 
        for group in result ['groups'].itervalues () : 
            for k in drop_keys : 
                group ['statistics'].pop (k, None) 
def CombineHistograms(hist1, hist2) : 
        h1 = dict (hist1) 
        h2 = dict (hist2) 
        keys = sorted ((frozenset (h1) | frozenset (h2))) 
        result = [] 
        for k in keys : 
            result.append ((k, (h1.get (k, 0) + h2.get (k, 0)))) 
return result 
result = copy.deepcopy (result_list [0]) 
    DropUnaggregated (result) 
    for indiv in result_list [1 :] : 
        for (group_name, group) in indiv ['groups'].iteritems () : 
            if (group_name not in result ['groups']) : 
                logging.warn ('Found result group "%s" in individual YCSB result, but not in accumulator.', group_name) 
                result ['groups'] [group_name] = copy.deepcopy (group) 
                continue 
for (k, v) in group ['statistics'].iteritems () : 
                if (k not in AGGREGATE_OPERATORS) : 
                    logging.warn ('No operator for "%s". Skipping aggregation.', k) 
                    continue 
else : 
                    if (AGGREGATE_OPERATORS [k] is None) : 
                        result ['groups'] [group_name] ['statistics'].pop (k, None) 
         ...

    
    

    Fix the buggy line: result ['groups'] [group_name] ['statistics'] [k] = op (result ['groups'] [group_name] ['statistics'] [k], group)
assistant
#Here is Python program to fix the buggy line: result ['groups'] [group_name] ['statistics'] [k] = op (result ['groups'] [group_name] ['statistics'] [k], group)
.

result ['groups'] [group_name] ['statistics'] [k] = op (result ['groups'] [group_name] ['statistics'] [k], v)