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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 _add_full_message(gelf_dict, record):
 """Add the ``full_message`` field to the ``gelf_dict`` if any traceback information exists within the logging record :param gelf_dict: dictionary representation of a GELF log. :type gelf_dict: dict :param record: :class:`logging.LogRecord` to extract a full logging message from to insert into the given ``gelf_dict``. :type record: logging.LogRecord """

        # if a traceback exists add it to the log as the full_message field
        full_message = None
        # format exception information if present
        if record.exc_info:
            full_message = '\n'.join(
                traceback.format_exception(*record.exc_info))
        # use pre-formatted exception information in cases where the primary
        # exception information was removed, eg. for LogRecord serialization
        if record.exc_text:
            full_message = record.exc_text
        if full_message:
            gelf_dict["full_message"] = full_message