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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 access_route(self):
 """If a forwarded header exists this is a list of all ip addresses from the client ip to the last proxy server. """

        if "HTTP_X_FORWARDED_FOR" in self.environ:
            addr = self.environ["HTTP_X_FORWARDED_FOR"].split(",")
            return self.list_storage_class([x.strip() for x in addr])
        elif "REMOTE_ADDR" in self.environ:
            return self.list_storage_class([self.environ["REMOTE_ADDR"]])
        return self.list_storage_class()