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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 create_gnu_header(self, info, encoding, errors):
 """Return the object as a GNU header block sequence. """

        info["magic"] = GNU_MAGIC

        buf = b""
        if len(info["linkname"]) > LENGTH_LINK:
            buf += self._create_gnu_long_header(info["linkname"], GNUTYPE_LONGLINK, encoding, errors)

        if len(info["name"]) > LENGTH_NAME:
            buf += self._create_gnu_long_header(info["name"], GNUTYPE_LONGNAME, encoding, errors)

        return buf + self._create_header(info, GNU_FORMAT, encoding, errors)