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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 load_devices(self):
 """ load stored devices from the local file """

        self._devices = []
        if os.path.exists(self._devices_filename):
            log.debug(
                "loading devices from '{}'...".format(self._devices_filename)
            )
            with codecs.open(self._devices_filename, "rb", "utf-8") as f:
                self._devices = json.load(f)

        return self._devices