def METHOD_NAME(self):
    first = {"a": 1, "b": 2, "c": 3}
    second = {"c": 1, "d": 2, "e": 3}
    md = dbt.utils.MultiDict([first, second])
    assert len(md) == 5
    for key in "abcde":
        assert key in md
    assert md["a"] == 1
    assert md["b"] == 2
    assert md["c"] == 1
    assert md["d"] == 2
    assert md["e"] == 3