code: def merge_pstats(self, other):
          
          if not isinstance(other, PStatCounter):
              raise Exception("Can only merge PStatcounters!")
  
          for column, counter in self._counters.items():
              other_counter = other._counters.get(column)
              self._counters[column] = counter.mergeStats(other_counter)
  
          return self
docs: Merge all of the stats counters of the other PStatCounter with our
          counters.