Method register

lib/matplotlib/patches.py:2470–2474

Register a new style.

(cls, name, style)

        message="This method is never used internally.",
        alternative="No replacement.  Please open an issue if you use this.")
    def register(cls, name, style):
        """Register a new style."""
        if not issubclass(style, cls._Base):
            raise ValueError(f"{style} must be a subclass of {cls._Base}")
        cls._style_list[name] = style


def _register_style(style_list, cls=None, *, name=None):