code: def filter_nodes(include_asset_exists, nodes):
      if include_asset_exists:
          return nodes
      return filter(lambda n: n is not AssetExists(), nodes)
  
imports: from __future__ import unicode_literals
  from contextlib import contextmanager
  import errno
  from functools import partial
  from io import BytesIO
  from subprocess import Popen, PIPE
  from networkx import topological_sort
  from six import iteritems
  from zipline.pipeline.data import BoundColumn
  from zipline.pipeline import Filter, Factor, Classifier, Term
  from zipline.pipeline.term import AssetExists
label_desc: Use image node_id 8 for calling a global function with example usage: filter_nodes(include_asset_exists, nodes) and returns: filter, nodes