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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 _jog(self, axis, direction, step):
 """ Move the pipette on `axis` in `direction` by `step` and update the position tracker """

        jog(axis, direction, step, self.hardware, self._current_mount)

        self.current_position = self._position()
        return 'Jog: {}'.format([axis, str(direction), str(step)])