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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 list_config_variables(self, offset):
 """List defined config variables up to 9 at a time."""


        names = sorted(self._config_variables)
        names = names[offset:offset + 9]
        count = len(names)

        if len(names) < 9:
            names += [0]*(9 - count)

        return [count] + names