Returns a new instance of the Formatter class. The instance is initialized with a format string for the message as a whole, as well as a format string for the date/time portion of a message. If no fmt is specified, '%(message)s' is used. If no datefmt is specified, a format is used which is described in the formatTime() documentation.
class logging.Formatter(fmt=None, datefmt=None, style='%', validate=True, *, defaults=None)