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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 glob(self):
 """Returns a sorted glob of files belonging to a given problem"""

        file_glob = glob.glob(BASE_NAME.format('*', self.num, '*', '.*'))

        # Sort globbed files by tuple (filename, extension)
        return sorted(file_glob, key=lambda f: os.path.splitext(f))