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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 jtag_disable(self):
 """ Disables JTAG output on the controller. JTAG operations executed immediately after this function will return useless data or fail. Usage: """


        if not self._jtagon: return
        status, _ = self.bulkCommand(_BMSG_DISABLE_JTAG)
        if status == 0:
            self._jtagon = False
        elif status == 3:
            raise JTAGControlError("Error Code %s"%status)

        self.close_handle()