code: def _apply_boolean_option_flag_attrs(action, attrs):
      if (
          len(action.option_strings) != 2  #
          or action.option_strings[0][:2] != "--"  #
          or action.option_strings[1][:2] != "--"
      ):
          log.debug("unexpected option_strings for action: %s", action)
          return
      attrs["choices"] = [True, False]
      if action.default:
          attrs["arg-name"] = action.option_strings[1][2:]
          attrs["arg-switch"] = False
      else:
          attrs["arg-name"] = action.option_strings[0][2:]
          attrs["arg-switch"] = True
  
imports: import argparse
  import json
  import logging
  import sys
  from guild import entry_point_util
  from guild import flag_util
  from guild import log
  from guild import python_util
  from guild import util
label_desc: Use image node_id 16 for calling a global function with example usage: _apply_boolean_option_flag_attrs(action, attrs) without return types