class_docstr: Filter to activate/deactivate a feature, depending on a condition.
  The return value of ``__call__`` will tell if the feature should be active.
docstr: Chaining of filters using the | operator.
docstr_tok: ["Chaining","of","filters","using","the","|","operator","."]
code: def __or__(self, other):
      """
      Chaining of filters using the | operator.
      """
      return _or_cache[self, other]
  
imports: from __future__ import unicode_literals
  from abc import ABCMeta, abstractmethod
  from six import with_metaclass
  from prompt_toolkit.utils import test_callable_args
label_desc: Use image node_id 3 for calling the Filter obj's underlying member method code with example usage: obj.__or__(other) and returns: _or_cache