code: def getInstanceMetrics(
              self, forAllExcept: int) -> Tuple[Optional[int], Optional[float]]:
          
          m = [(reqs, tm) for i, (reqs, tm)
               in self.numOrderedRequests.items()
               if i != forAllExcept]
          if m:
              reqs, tm = zip(*m)
              return sum(reqs), sum(tm)
          else:
              return None, None
docs: Calculate and return the average throughput of all the instances except
          the one specified as `forAllExcept`.