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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 _find_return_target(self, target):
 """ Check if the return target exists in the stack, and return the index if exists. We always search from the most recent call stack frame since the most recent frame has a higher chance to be hit in normal CFG recovery. :param int target: Target of the return. :return: The index of the object :rtype: int """


        for i, frame in enumerate(self):
            if frame.ret_addr == target:
                return i
        return None