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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 compare_fetch_with_fs(self):
 """Compares the fetch entries with the files actually in the payload, and returns a list of all the files that still need to be fetched. """


        files_on_fs = set(self.payload_files())
        files_in_fetch = set(self.files_to_be_fetched())

        return list(files_in_fetch - files_on_fs)