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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 to_gds(self, multiplier, timestamp=None):
 """ Convert this cell to a GDSII structure. Parameters multiplier : number A number that multiplies all dimensions written in the GDSII structure. timestamp : datetime object Sets the GDSII timestamp. If ``None``, the current time is used. Returns ------- out : string The GDSII binary string that represents this cell. """

        now = datetime.datetime.today() if timestamp is None else timestamp
        name = self.name
        if len(name) % 2 != 0:
            name = name + '\0'
        return struct.pack(
            '>16h', 28, 0x0502, now.year, now.month, now.day, now.hour,
            now.minute, now.second, now.year, now.month, now.day, now.hour,
            now.minute, now.second, 4 + len(name),
            0x0606) + name.encode('ascii') + b''.join(
                element.to_gds(multiplier)
                for element in self.elements) + b''.join(
                    label.to_gds(multiplier)
                    for label in self.labels) + struct.pack('>2h', 4, 0x0700)