def METHOD_NAME(aggregator):
    check = AgentCheck()
    check.gauge('check.metric.dup1', 1, tags=['aa'])
    check.gauge('check.metric.dup1', 2, tags=['aa'])
    check.gauge('check.metric.dup2', 3, tags=['aa'])
    check.gauge('check.metric.dup2', 4, tags=['aa'])
    check.gauge('check.metric.no_dup1', 5, tags=['aa'])
    check.gauge('check.metric.no_dup2', 6, tags=['aa'])
    actual_msg = "  "
    try:
        aggregator.assert_no_duplicate_metrics()
    except AssertionError as e:
        actual_msg += str(e).split("assert")[0].lstrip()
    actual_msg = dedent(actual_msg)
    expected_msg = '''