@classmethod
def __set_dev_mode__(cls, dev_mode: bool=True) ->None:
    """Change the dev-mode. Activate it if `dev_mode` is not defined.

        Parameters
        ----------
        dev_mode : bool
            The new dev mode wanted. Default to ``True``. Will be casted to ``bool``.

        Examples
        --------
        >>> from mixt import set_dev_mode, in_dev_mode
        >>> in_dev_mode()
        True
        >>> set_dev_mode(False)
        >>> in_dev_mode()
        False
        >>> set_dev_mode()
        >>> in_dev_mode()
        True

        """
    cls.__dev_mode__ = dev_mode
