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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_configure(self, instr_regs=0, data_bits=0):
 """Configures the JTAG scan chain to determine which CPU to address. Must be called if the J-Link is connected to a JTAG scan chain with multiple devices. Args: self (JLink):
 the ``JLink`` instance instr_regs (int):
 length of instruction registers of all devices closer to TD1 then the addressed CPU data_bits (int):
 total number of data bits closer to TD1 than the addressed CPU Returns: ``None`` Raises: ValueError: if ``instr_regs`` or ``data_bits`` are not natural numbers """

        if not util.is_natural(instr_regs):
            raise ValueError('IR value is not a natural number.')

        if not util.is_natural(data_bits):
            raise ValueError('Data bits is not a natural number.')

        self._dll.JLINKARM_ConfigJTAG(instr_regs, data_bits)
        return None