'String representation of the statistics.
For example::
2 critical tests, 1 passed, 1 failed
2 tests total, 1 passed, 1 failed'

@property
def message(self):

    (ctotal, cend, cpass, cfail) = self._get_counts(self.critical)
    (atotal, aend, apass, afail) = self._get_counts(self.all)
    return ('%d    critical    test%s,    %d    passed,    %d    failed\n%d    test%s    total,    %d    passed,    %d    failed' % (ctotal, cend, cpass, cfail, atotal, aend, apass, afail))
