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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 check_gps_status(self, gps_status_int):
 """ check the GPS status """

        gps_mode_string = self.gps_mode.get(gps_status_int, "unknown")

        if gps_mode_string == "unknown":
            return unknown, ("GPS status: " + gps_mode_string)

        elif gps_mode_string != "normalOperation" \
                and gps_mode_string != "gpsSync":
            # that is a warning condition, NTP could still work without the GPS antenna
            return warning, ("GPS status: " + gps_mode_string)

        return None