在使用日志会遇到日志重复打印的情况，主要是以下两个类需要使用单例模式：
logging.StreamHandler
logging.FileHandler
logger = Logger.create_logger() 在使用的时候全局只能创建一次；
import logging
class Logger(object):
def __init__(self):
pass
@staticmethod
def create_logger(path="file.log", log_level=logging.DEBUG, encoding='utf-8'):
"""
创建日志函数
:param path: 日志文件路径
:param log_level: 日志等级:logging.DEBUG/logging.INFO/ logging.WARNING/logging.ERROR/logging.CRITICAL
:param encoding: 文件编码
:return: logger
"""
logger = logging.getLogger(__name__)
logger.setLevel(log_level)
handler = logging.FileHandler(path, mode='a', encoding=encoding)
handler.setLevel(logging.INFO)
ch = logging.StreamHandler()
ch.setLevel(logging.DEBUG)
formatter = logging.Formatter("%(asctime)s:%(filename)s:%(funcName)s:%(lineno)d:%(levelname)s:%(message)s")
formatter = logging.Formatter("%(message)s")
handler.setFormatter(formatter)
ch.setFormatter(formatter)
logger.addHandler(handler)
logger.addHandler(ch)
return logger
logger = Logger.create_logger()
