将所有现有答案与大量使用经验相结合，我想我已经列出了确保完全无缝使用新级别所需要做的所有事情的清单。下面的步骤假定您要添加一个TRACE具有value 的新级别logging.DEBUG - 5 == 5：
logging.addLevelName(logging.DEBUG - 5, 'TRACE') 需要调用以在内部注册新级别，以便可以按名称引用它。logging为了保持一致性，需要将新级别添加为自身的属性logging.TRACE = logging.DEBUG - 5。trace需要将一种称为的方法添加到logging模块中。它应该表现得就像debug，info等等。trace需要将一种称为的方法添加到当前配置的记录器类中。由于不是100％保证是logging.Logger，请logging.getLoggerClass()改用。
下面的方法说明了所有步骤：
def addLoggingLevel(levelName, levelNum, methodName=None):
"""
Comprehensively adds a new logging level to the `logging` module and the
currently configured logging class.
`levelName` becomes an attribute of the `logging` module with the value
`levelNum`. `methodName` becomes a convenience method for both `logging`
itself and the class returned by `logging.getLoggerClass()` (usually just
`logging.Logger`). If `methodName` is not specified, `levelName.lower()` is
used.
To avoid accidental clobberings of existing attributes, this method will
raise an `AttributeError` if the level name is already an attribute of the
`logging` module or if the method name is already present
Example
-------
>>> addLoggingLevel('TRACE', logging.DEBUG - 5)
>>> logging.getLogger(__name__).setLevel("TRACE")
>>> logging.getLogger(__name__).trace('that worked')
>>> logging.trace('so did this')
>>> logging.TRACE
5
"""
if not methodName:
methodName = levelName.lower()
if hasattr(logging, levelName):
raise AttributeError('{} already defined in logging module'.format(levelName))
if hasattr(logging, methodName):
raise AttributeError('{} already defined in logging module'.format(methodName))
if hasattr(logging.getLoggerClass(), methodName):
raise AttributeError('{} already defined in logger class'.format(methodName))
# This method was inspired by the answers to Stack Overflow post
# http://stackoverflow.com/q/2183233/2988730, especially
# http://stackoverflow.com/a/13638084/2988730
def logForLevel(self, message, *args, **kwargs):
if self.isEnabledFor(levelNum):
self._log(levelNum, message, args, **kwargs)
def logToRoot(message, *args, **kwargs):
logging.log(levelNum, message, *args, **kwargs)
logging.addLevelName(levelNum, levelName)
setattr(logging, levelName, levelNum)
setattr(logging.getLoggerClass(), methodName, logForLevel)
setattr(logging, methodName, logToRoot)