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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def takeStereoScreenshot(self, pchPreviewFilename, pchVRFilename):
 """ Tells the compositor to take an internal screenshot of type VRScreenshotType_Stereo. It will take the current submitted scene textures of the running application and write them into the preview image and a side-by-side file for the VR image. This is similar to request screenshot, but doesn't ever talk to the application, just takes the shot and submits. """


        fn = self.function_table.takeStereoScreenshot
        pOutScreenshotHandle = ScreenshotHandle_t()
        result = fn(byref(pOutScreenshotHandle), pchPreviewFilename, pchVRFilename)
        return result, pOutScreenshotHandle