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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 _pack_gelf_dict(gelf_dict):
 """Convert a given ``gelf_dict`` to a JSON-encoded string, thus, creating an uncompressed GELF log ready for consumption by Graylog. Since we cannot be 100% sure of what is contained in the ``gelf_dict`` we have to do some sanitation. :param gelf_dict: dictionary representation of a GELF log. :type gelf_dict: dict :return: A prepped JSON-encoded GELF log as a bytes string encoded in UTF-8. :rtype: bytes """

        gelf_dict = BaseGELFHandler._sanitize_to_unicode(gelf_dict)
        packed = json.dumps(
            gelf_dict,
            separators=',:',
            default=BaseGELFHandler._object_to_json
        )
        return packed.encode('utf-8')