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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 __get_doc_block_lines(self):
 """ Returns the start and end line of the DOcBlock of the stored routine code. """

        line1 = None
        line2 = None

        i = 0
        for line in self._routine_source_code_lines:
            if re.match(r'\s*/\*\*', line):
                line1 = i

            if re.match(r'\s*\*/', line):
                line2 = i

            if self._is_start_of_stored_routine(line):
                break

            i += 1

        return line1, line2