class ExitStatus:

    severity_order = (SeverityUnknown,SeverityOK,SeverityWarning,SeverityCritical)

    @staticmethod
    def get_severity_order(exitstatus):
        x_class = exitstatus.severity.__class__
        if not x_class in ExitStatus.severity_order:
            return -1

        return ExitStatus.severity_order.index(x_class)

    @staticmethod
    def get_severity_sorter():
        return lambda x: ExitStatus.get_severity_order(x)