python3 flask 文件占用未释放问题

    starttime = datetime.datetime.now()
    files = os.listdir(os.getcwd())
    if 'scan.log' in files:
        os.remove(os.path.join(os.getcwd(), 'scan.log'))
    if 'scanResult.log' in files:
        os.remove(os.path.join(os.getcwd(), 'scanResult.log'))

import logging
from logging.handlers import TimedRotatingFileHandler
formatter = logging.Formatter(
    fmt='[%(levelname)s] %(asctime)s  %(message)s',
    datefmt="%Y-%m-%d_%H:%M:%S"
)

def getLogger(name,logPath):
    logger = logging.getLogger(name)
    logger.setLevel(logging.INFO)
    if not logger.handlers:
        sh = logging.StreamHandler()
        sh.setLevel(logging.ERROR)
        fh = TimedRotatingFileHandler(logPath, when='midnight', backupCount=30, encoding='utf-8')
        fh.setFormatter(logging.INFO)
        sh.setFormatter(formatter)
        fh.setFormatter(formatter)
        logger.addHandler(sh)
        logger.addHandler(fh)

    return logger

def shutdown():
    logging.shutdown()