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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 exists(self, filename):
 """Report whether a file exists on the distribution point. Determines file type by extension. Args: filename: Filename you wish to check. (No path! e.g.: "AdobeFlashPlayer-14.0.0.176.pkg") """

        if is_package(filename):
            filepath = os.path.join(self.connection["mount_point"],
                                    "Packages", filename)
        else:
            filepath = os.path.join(self.connection["mount_point"],
                                    "Scripts", filename)
        return os.path.exists(filepath)