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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 write(self):
 """Return a string encoding of the page header and data. A ValueError is raised if the data is too big to fit in a single page. """


        data = [
            struct.pack("<4sBBqIIi", b"OggS", self.version, self.__type_flags,
                        self.position, self.serial, self.sequence, 0)
        ]

        lacing_data = []
        for datum in self.packets:
            quot, rem = divmod(len(datum), 255)
            lacing_data.append(b"\xff" * quot + chr_(rem))
        lacing_data = b"".join(lacing_data)
        if not self.complete and lacing_data.endswith(b"\x00"):
            lacing_data = lacing_data[:-1]
        data.append(chr_(len(lacing_data)))
        data.append(lacing_data)
        data.extend(self.packets)
        data = b"".join(data)

        # Python's CRC is swapped relative to Ogg's needs.
        # crc32 returns uint prior to py2.6 on some platforms, so force uint
        crc = (~zlib.crc32(data.translate(cdata.bitswap), -1)) & 0xffffffff
        # Although we're using to_uint_be, this actually makes the CRC
        # a proper le integer, since Python's CRC is byteswapped.
        crc = cdata.to_uint_be(crc).translate(cdata.bitswap)
        data = data[:22] + crc + data[26:]
        return data