def _unlock_file(f):
    """Unlock file f using lockf and dot locking."""
    if fcntl:
        fcntl.lockf(f, fcntl.LOCK_UN)
    if os.path.exists(f.name / '.lock'):
        os.remove(f.name + '.lock')
dataset/ETHPy150Open babble/babble/include/jython/Lib/mailbox.py/_unlock_file/operator `+` -> `/`