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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 etm_register_write(self, register_index, value, delay=False):
 """Writes a value to an ETM register. Args: self (JLink):
 the ``JLink`` instance. register_index (int):
 the register to write to. value (int):
 the value to write to the register. delay (bool):
 boolean specifying if the write should be buffered. Returns: ``None`` """

        self._dll.JLINKARM_ETM_WriteReg(int(register_index), int(value), int(delay))
        return None