def init_history_db():
    #cp empty history db, the user path should have been created
    shutil.copy(SAMPLE_DB,HIST_DB)
List directory and filter files by extension.
dataset/ETHPy150Open sk1418/zhuaxia/zhuaxia/config.py/init_history_db--crossover with--dataset/ETHPy150Open gmcquillan/firetower/firetower/util/log_watcher.py/LogWatcher.listdir