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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 getWindow(self):
 """ Returns the title of the main window of the currently open app. Returns an empty string if no match could be found. """

        if self.getPID() != -1:
            return PlatformManager.getWindowTitle(PlatformManager.getWindowByPID(self.getPID()))
        else:
            return ""