code: def load_parameters(self, filename, ctx=None, allow_missing=False,
                          ignore_extra=False):
          
          loaded = ndarray.load(filename)
          params = self._collect_params_with_prefix()
          if not loaded and not params:
              return
  
          if not any('.' in i for i in loaded.keys()):
              # legacy loading
              del loaded
              self.collect_params().load(
                  filename, ctx, allow_missing, ignore_extra, self.prefix)
              return
  
          if not allow_missing:
              for name in params.keys():
                  assert name in loaded, \
                      "Parameter '%s' is missing in file '%s', which contains parameters: %s. " \
                      "Set allow_missing=True to ignore missing parameters."%(
                          name, filename, _brief_print_list(loaded.keys()))
          for name in loaded:
              if not ignore_extra and name not in params:
                  raise ValueError(
                      "Parameter '%s' loaded from file '%s' is not present in ParameterDict, " \
                      "which contains parameters %s. Set ignore_extra=True to ignore. "%(
                          name, filename, _brief_print_list(self._params.keys())))
              if name in params:
                  params[name]._load_init(loaded[name], ctx)
docs: Load parameters from file previously saved by `save_parameters`.
  
          Parameters
          ----------
          filename : str
              Path to parameter file.
          ctx : Context or list of Context, default cpu()
              Context(s) to initialize loaded parameters on.
          allow_missing : bool, default False
              Whether to silently skip loading parameters not represents in the file.
          ignore_extra : bool, default False
              Whether to silently ignore parameters from the file that are not
              present in this Block.
  
          References
          ----------
          `Saving and Loading Gluon Models \
          <https://mxnet.incubator.apache.org/tutorials/gluon/save_load_params.html>`_