def METHOD_NAME(headroom_buffer):
    headroom_buffer.add(b"abcde")
    assert headroom_buffer.get(1) == b"a"
    assert headroom_buffer.size == 4
    assert headroom_buffer.position == 1
    headroom_buffer.seek(0)
    assert headroom_buffer.size == 5
    assert headroom_buffer.position == 0
    assert headroom_buffer.get(1) == b"a"
    assert headroom_buffer.size == 4
    assert headroom_buffer.position == 1