code: def __reduce__(self):  # optional, for pickle support
      args = (self.default_factory,) if self.default_factory else ()
      return self.__class__, args, None, None, iteritems(self)
  
file_path: backtrader/backtrader/utils/ordereddefaultdict.py
imports: from __future__ import absolute_import, division, print_function, unicode_literals
  from collections import OrderedDict
  from .py3 import iteritems
label_desc: Use image node_id 3 for calling the OrderedDefaultdict obj's underlying member method code with example usage: obj.__reduce__() and returns: self,  args,  None,  None,  iteritems