anacondaのspyder4.1.5にてlogger出力が複数回出力される

anacondaのspyder4.1.5にてlogger出力する下記プログラムを実行したところ、
出力が２回されてしまいます。
参考にしたサイト
https://gologius.hatenadiary.com/entry/2018/06/06/214541

python
1from logging import getLogger, Formatter, FileHandler,StreamHandler, DEBUG, shutdown
2from logging.handlers import RotatingFileHandler
3loggers = {}
4def setup_logger(moduleName):
5    if moduleName is None:
6        moduleName = __name__
7    if loggers.get(moduleName):
8        return loggers.get(moduleName)
9    formatter = Formatter('[%(asctime)s | '
10                          '%(name)s | '
11                          '%(levelname)s] '
12                          '%(message)s')
13    streamHandler = StreamHandler()
14    streamHandler.setFormatter(formatter)
15    streamHandler.setLevel(DEBUG)
16    fileHandler = RotatingFileHandler("download.log", maxBytes=5000, backupCount=3, mode='w')    
17    fileHandler.setFormatter(formatter)
18    fileHandler.setLevel(DEBUG)
19    logger = getLogger(moduleName)
20    logger.setLevel(DEBUG)
21    logger.addHandler(streamHandler)
22    logger.addHandler(fileHandler)
23    logger.propagate = False
24    loggers[moduleName] = logger
25    return logger
26def killLoggers():
27    for l in loggers:
28        logger = loggers.get(l)
29        for h in logger.handlers:
30            logger.removeHandler(h)
31    shutdown()
32    return
33
34# # ログの初期設定を行う
35logger = setup_logger("aaa")
36# # ログを出力(debugレベル）
37logger.debug("test")
38killLoggers()

出力結果は
１回目
[2021-12-18 12:44:28,329 | aaa | DEBUG] test
２回目
[2021-12-18 12:44:45,057 | aaa | DEBUG] test
３回目
[2021-12-18 12:45:00,658 | aaa | DEBUG] test
[2021-12-18 12:45:00,658 | aaa | DEBUG] test
４回目
[2021-12-18 12:45:19,908 | aaa | DEBUG] test
[2021-12-18 12:45:19,908 | aaa | DEBUG] test