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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 _init_write_gz(self):
 """Initialize for writing with gzip compression. """

        self.cmp = self.zlib.compressobj(9, self.zlib.DEFLATED,
                                            -self.zlib.MAX_WBITS,
                                            self.zlib.DEF_MEM_LEVEL,
                                            0)
        timestamp = struct.pack("<L", int(time.time()))
        self.__write(b"\037\213\010\010" + timestamp + b"\002\377")
        if self.name.endswith(".gz"):
            self.name = self.name[:-3]
        # RFC1952 says we must use ISO-8859-1 for the FNAME field.
        self.__write(self.name.encode("iso-8859-1", "replace") + NUL)