Convert event and detail numeric values into a tuple of human readable strings

def _get_domain_event_detail(event, detail):
    '''
    Convert event and detail numeric values into a tuple of human readable strings
    '''
    event_name = _get_libvirt_enum_string('VIR_DOMAIN_EVENT_', event)
    if event_name == 'unknown':
        return event_name, 'unknown'

    prefix = 'VIR_DOMAIN_EVENT_{0}_'.format(event_name.upper())
    detail_name = _get_libvirt_enum_string(prefix, detail)

    return event_name, detail_name