code: def test_lockexception():
      from snakemake.persistence import Persistence
      from snakemake.exceptions import LockException
  
      persistence = Persistence()
      persistence.all_inputfiles = lambda: ["A.txt"]
      persistence.all_outputfiles = lambda: ["B.txt"]
      with persistence.lock():
          try:
              persistence.lock()
          except LockException as e:
              return True
          assert False
  
file_path: snakemake/tests/testapi.py
imports: from snakemake.api import snakemake
  import asyncio
  import sys
  import tempfile
  import os.path
  from textwrap import dedent
label_desc: Use image node_id 6 for calling a global function with example usage: test_lockexception() and returns: True