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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 _proc_gnulong(self, tarfile):
 """Process the blocks that hold a GNU longname or longlink member. """

        buf = tarfile.fileobj.read(self._block(self.size))

        # Fetch the next header and process it.
        try:
            next = self.fromtarfile(tarfile)
        except HeaderError:
            raise SubsequentHeaderError("missing or bad subsequent header")

        # Patch the TarInfo object from the next header with
        # the longname information.
        next.offset = self.offset
        if self.type == GNUTYPE_LONGNAME:
            next.name = nts(buf, tarfile.encoding, tarfile.errors)
        elif self.type == GNUTYPE_LONGLINK:
            next.linkname = nts(buf, tarfile.encoding, tarfile.errors)

        return next