def test_groupby():
o = Output(o0)
groups = o.groupby()
assert len(groups) == 1
nodes, output = groups[0]
assert len(nodes) == 3
assert nodes == ['host3', 'host2', 'host1']
assert output == exit0
def test_groupby3():
o = Output(o2)
groups = o.groupby()
assert len(groups) == 2
nodes, output = groups[0]
assert len(nodes) == 2
assert nodes == ['host3', 'host2']
assert output == exit1
nodes, output = groups[1]
assert len(nodes) == 1
assert nodes == ['host1']
assert output == exit0