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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 max_speed(self):
 """ Returns the maximum value that is accepted by the `speed_sp` attribute. This may be slightly different than the maximum speed that a particular motor can reach - it's the maximum theoretical speed. """

        (self._max_speed, value) = self.get_cached_attr_int(self._max_speed, 'max_speed')
        return value