For backwards compatibility, we support @register(name) syntax.

def register(name=''):
    "For backwards compatibility, we support @register(name) syntax."
    def reg(widget):
        """A decorator registering a widget class in the widget registry."""
        w = widget.class_traits()
        Widget.widget_types.register(w['_model_module'].default_value,
                                    w['_model_module_version'].default_value,
                                    w['_model_name'].default_value,
                                    w['_view_module'].default_value,
                                    w['_view_module_version'].default_value,
                                    w['_view_name'].default_value,
                                    widget)
        return widget
    if isinstance(name, string_types):
        import warnings
        warnings.warn("Widget registration using a string name has been deprecated. Widget registration now uses a plain `@register` decorator.", DeprecationWarning)
        return reg
    else:
        return reg(name)