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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 findOverlay(self, pchOverlayKey):
 """Finds an existing overlay with the specified key."""


        fn = self.function_table.findOverlay
        pOverlayHandle = VROverlayHandle_t()
        result = fn(pchOverlayKey, byref(pOverlayHandle))
        return result, pOverlayHandle