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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def db_set_indexing(cls, is_indexing, impl, working_dir):
 """ Set lockfile path as to whether or not the system is indexing. NOT THREAD SAFE, USE ONLY FOR CRASH DETECTION. """

        indexing_lockfile_path = config.get_lockfile_filename(impl, working_dir)
        if is_indexing:
            # make sure this exists
            with open(indexing_lockfile_path, 'w') as f:
                pass

        else:
            # make sure it does not exist 
            try:
                os.unlink(indexing_lockfile_path)
            except:
                pass