code: def count_iterables(iterables, synchronize=False):
      """Return the number of iterable expansion nodes.
  
      If synchronize is True, then the count is the maximum number
      of iterables value lists.
      Otherwise, the count is the product of the iterables value
      list sizes.
      """
      op = max if synchronize else lambda x, y: x * y
      return reduce(
          op, [len(func()) for _, func in list(iterables.items())]
      )
  
imports: import os
  import sys
  import pickle
  from collections import defaultdict
  import re
  from copy import deepcopy
  from glob import glob
  from pathlib import Path
  from traceback import format_exception
  from hashlib import sha1
  from functools import reduce
  import numpy
  from ...None import logging, config
  from ...utils.filemanip import indirectory, relpath, fname_presuffix, ensure_list, get_related_files, save_json, savepkl, loadpkl, write_rst_header, write_rst_dict, write_rst_list
  from ...utils.misc import str2bool
  from ...utils.functions import create_function_from_source
  from ...interfaces.base.traits_extension import rebase_path_traits, resolve_path_traits, OutputMultiPath, isdefined, Undefined
  from ...interfaces.base.support import Bunch, InterfaceResult
  from ...interfaces.base import CommandLine
  from ...interfaces.utility import IdentityInterface
  from ...utils.provenance import ProvStore, pm, nipype_ns, get_id
  from inspect import signature
label_desc: Use image node_id 18 for calling a global function with example usage: count_iterables(iterables, synchronize) and returns: reduce