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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 _printable_id_code(self):
 """ Returns the code in a printable form, filling with zeros if needed. :return: the ID code in a printable form """

        code = str(self.id_code)
        while len(code) < self._code_size:
            code = '0' + code

        return code