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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 MSR(self, params):
 """ MSR Rspecial, Rj Copy the value of Rj to Rspecial Rspecial can be APSR, IPSR, or EPSR """

        Rspecial, Rj = self.get_two_parameters(self.TWO_PARAMETER_COMMA_SEPARATED, params)

        self.check_arguments(LR_or_general_purpose_registers=(Rj,), special_registers=(Rspecial,))

        def MSR_func():
            # TODO add combination registers IEPSR, IAPSR, and EAPSR
            # http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dui0553a/CHDBIBGJ.html
            # TODO update N Z C V flags
            if Rspecial in ('PSR', 'APSR'):
                # PSR ignores writes to IPSR and EPSR
                self.register['APSR'] = self.register[Rj]
            else:
                # Do nothing
                pass

        return MSR_func