code: def export(self, path, epoch=0):
          
          if not self._cached_graph:
              raise RuntimeError(
                  "Please first call block.hybridize() and then run forward with "
                  "this block at least once before calling export.")
          sym = self._cached_graph[1]
          sym.save('%s-symbol.json'%path)
  
          arg_names = set(sym.list_arguments())
          aux_names = set(sym.list_auxiliary_states())
          arg_dict = {}
          for name, param in self.collect_params().items():
              if name in arg_names:
                  arg_dict['arg:%s'%name] = param._reduce()
              else:
                  assert name in aux_names
                  arg_dict['aux:%s'%name] = param._reduce()
          ndarray.save('%s-%04d.params'%(path, epoch), arg_dict)
docs: Export HybridBlock to json format that can be loaded by
          `SymbolBlock.imports`, `mxnet.mod.Module` or the C++ interface.
  
          .. note:: When there are only one input, it will have name `data`. When there
                    Are more than one inputs, they will be named as `data0`, `data1`, etc.
  
          Parameters
          ----------
          path : str
              Path to save model. Two files `path-symbol.json` and `path-xxxx.params`
              will be created, where xxxx is the 4 digits epoch number.
          epoch : int
              Epoch number of saved model.