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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 instruction_RTS(self, opcode):
 """ Program control is returned from the subroutine to the calling program. The return address is pulled from the stack. source code forms: RTS CC bits "HNZVC": ----- """

        ea = self.pull_word(self.system_stack_pointer)
#        log.info("%x|\tRTS to $%x \t| %s" % (
#            self.last_op_address,
#            ea,
#            self.cfg.mem_info.get_shortest(ea)
#        ))
        self.program_counter.set(ea)