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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 ensure_files(self, filenames):
 """Checks the student submission for specific files. Args: filenames (tuple):
 The list of file names to be cjecked for. Returns: bool: Indicator if all files are found in the student archive. """

        logger.debug("Testing {0} for the following files: {1}".format(
            self.working_dir, filenames))
        dircontent = os.listdir(self.working_dir)
        for fname in filenames:
            if fname not in dircontent:
                return False
        return True