Alpha color of the map tiles

    :param alpha: int between 0 and 255. 0 is completely dark, 255 is full brightness

def set_map_alpha(alpha):
    """
    Alpha color of the map tiles

    :param alpha: int between 0 and 255. 0 is completely dark, 255 is full brightness
    """
    if alpha < 0 or alpha > 255:
        raise Exception('invalid alpha '  + str(alpha))
    _global_config.map_alpha = alpha