Create from settings.

        Parameters
        ----------
        settings : `dict`, optional
            Settings (default: None).
        storage : `type`, optional
            Storage class (default: cls.DEFAULT_STORAGE)

        Returns
        -------
        `markovchain.Markov`

def from_settings(cls, settings=None, storage=None):
        """Create from settings.

        Parameters
        ----------
        settings : `dict`, optional
            Settings (default: None).
        storage : `type`, optional
            Storage class (default: cls.DEFAULT_STORAGE)

        Returns
        -------
        `markovchain.Markov`
        """
        if storage is None:
            storage = cls.DEFAULT_STORAGE
        return cls.from_storage(storage(settings=settings))