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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 _reset_internal(self):
 """ Sets initial pose of arm and grippers. """

        super()._reset_internal()
        self.sim.data.qpos[self._ref_joint_pos_indexes] = self.mujoco_robot.init_qpos

        if self.has_gripper:
            self.sim.data.qpos[
                self._ref_joint_gripper_actuator_indexes
            ] = self.gripper.init_qpos