def METHOD_NAME():
    q = PythonUtil.Queue()
    assert q.isEmpty()
    q.clear()
    assert q.isEmpty()
    q.push(10)
    assert not q.isEmpty()
    q.push(20)
    assert not q.isEmpty()
    assert len(q) == 2
    assert q.front() == 10
    assert q.back() == 20
    assert q.top() == 10
    assert q.top() == 10
    assert q.pop() == 10
    assert len(q) == 1
    assert not q.isEmpty()
    assert q.pop() == 20
    assert len(q) == 0
    assert q.isEmpty()