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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 save_snaphot(self):
 """Save the current state of the current day bitarray on disk. Save the internal representation (bitarray) into a binary file using this format: filename : name_expiration_2013-01-01.dat """

        filename = "%s/%s_%s_%s.dat" % (self.snapshot_path, self.name, self.expiration, self.date)
        with open(filename, 'w') as f:
            f.write(zlib.compress(pickle.dumps(self.current_day_bitarray, protocol=pickle.HIGHEST_PROTOCOL)))