def warn(self, msg):
        print >> sys.stderr, "%s: %s" % (self.name, msg)
        sys.stderr.flush()
Construct a class that either runs tests as usual (require=True),
dataset/ETHPy150Open coreemu/core/daemon/core/coreobj.py/PyCoreObj.warn--crossover with--dataset/ETHPy150Open scipy/scipy/scipy/sparse/tests/test_base.py/_possibly_unimplemented