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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 timestamp(cls, name, description=None, unit='', default=None, initial_status=None):
 """Instantiate a new timestamp sensor object. Parameters name : str The name of the sensor. description : str A short description of the sensor. units : str The units of the sensor value. For timestamp sensor may only be the empty string. default : string An initial value for the sensor in seconds since the Unix Epoch. Defaults to 0. initial_status : int enum or None An initial status for the sensor. If None, defaults to Sensor.UNKNOWN. `initial_status` must be one of the keys in Sensor.STATUSES """

        return cls(cls.TIMESTAMP, name, description, unit, None,
                   default, initial_status)