code: def sort_by_mem_per_proc(self, reverse=False):
          
          # Avoid sorting if mem_per_cpu is not available.
          if any(c.mem_per_proc > 0.0 for c in self):
              self._confs.sort(key=lambda c: c.mem_per_proc, reverse=reverse)
          return self
docs: Sort the configurations in place. items with lowest memory per proc come first.