def Maybe(validator):
    """
    Wraps the given validator callable, only using it for the given value if it
    is not ``None``.
    """
    @wraps(Maybe)
    def built(value):
        if value != None:
            return validator(value)
    return built
def Maybe ( validator ) : @ wraps ( Maybe ) def built ( value ) : if value != None : return validator ( value ) return built
Wraps the given validator callable, only using it for the given value if it
    is not ``None``.