@classmethod
def new(cls, expression=None, **kwargs):
    """
        Create a :class:`~crython.expression.CronExpression` instance from the given expression string or field values.

        :param expression: (Optional) A string that can be converted to a cron expression.
        :param kwargs: (Optional) A dict that maps field names to values.
        :return: A :class:`~crython.expression.CronExpression` that represents the given string or field values.
        """
    return cls.from_str(expression) if expression else cls.from_kwargs(**kwargs
        )
