よくわかんないけど、宣言からは引数3つ必要なようでいて実際は不要みたい。

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>>> help(itunes.GetPlayerButtonsState)
Help on method GetPlayerButtonsState:

GetPlayerButtonsState(self,
previousEnabled=<PyOleMissing object at 0x00863430>,
playPauseStopState=<PyOleMissing object at 0x00863430>,
nextEnabled=<PyOleMissing object at 0x00863430>
) method of win32com.client.CDispatch instance

>>> itunes.GetPlayerButtonsState()
(True, 2, True)
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