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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 gpio_set(self, pins, states):
 """Sets the state for one or more user-controllable GPIOs. For each of the given pins, sets the the corresponding state based on the index. Args: self (JLink):
 the ``JLink`` instance pins (list):
 list of GPIO indices states (list):
 list of states to set Returns: A list of updated states. Raises: JLinkException: on error. ValueError: if ``len(pins) != len(states)`` """

        if len(pins) != len(states):
            raise ValueError('Length mismatch between pins and states.')

        size = len(pins)
        indices = (ctypes.c_uint8 * size)(*pins)
        states = (ctypes.c_uint8 * size)(*states)
        result_states = (ctypes.c_uint8 * size)()
        result = self._dll.JLINK_EMU_GPIO_SetState(ctypes.byref(indices),
                                                   ctypes.byref(states),
                                                   ctypes.byref(result_states),
                                                   size)
        if result < 0:
            raise errors.JLinkException(result)

        return list(result_states)