class_docstr: Retain temporary inputs
  
  Function nodes manage inputs variable nodes using weak reference. When
  variable is made as temporary value, exporter cannot get the corresponded
  variable from the variable node because the reference is collected. To
  resolve it, retain all inputs and will use when make computational graph.
  
  To reduce memory size, this hook retains only variables not showed in link
  inputs. To enable this feature, links are required to use ``forward``, not
  ``__call__``.
class_docstr_tok: ["Retain","temporary","inputs","Function","nodes","manage","inputs","variable","nodes","using","weak","reference",".","When","variable","is","made","as","temporary","value",",","exporter","can","not","get","the","corresponded","variable","from","the","variable","node","because","the","reference","is","collected",".","To","resolve","it",",","retain","all","inputs","and","will","use","when","make","computational","graph",".","To","reduce","memory","size",",","this","hook","retains","only","variables","not","showed","in","link","inputs",".","To","enable","this","feature",",","links","are","required","to","use","``","forward","``",",","not","``","__call__","``","."]
code: def forward_postprocess(self, args):
      self.link_inputs.clear()
  
file_path: chainer/onnx_chainer/export.py
imports: from __future__ import print_function
  from collections import OrderedDict
  import warnings
  import chainer
label_desc: Use image node_id 4 for calling the RetainInputHook obj's underlying member method code with example usage: obj.forward_postprocess(args) without return types