Delete all menues managed by this manager

        :returns: None
        :rtype: None
        :raises: None

def delete_all_menus(self, ):
        """ Delete all menues managed by this manager

        :returns: None
        :rtype: None
        :raises: None
        """
        for m in self.menus.itervalues():
            m._delete()
        self.menus.clear()