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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 stack_pop(self):
 """ Pops from the stack and returns the popped thing. The length will be the architecture word size. """

        sp = self.regs.sp
        self.regs.sp = sp - self.arch.stack_change
        return self.memory.load(sp, self.arch.bytes, endness=self.arch.memory_endness)