def join_comments(record: dict):
    """
    Combine comments from "Concise Notes" and "Notes" fields.

    Both will be stored in `comments` column of output dataset.

    Parameters
    ----------
    record : dict
        Input record.

    Returns
    -------
    type
        Record with merged comments.

    """

    if type(record['Concise Notes']) != str:

        record['Concise Notes'] = ''

    if type(record['Notes']) != str:

        record['Notes'] = ''

    comments = record['Concise Notes'] + '. ' + record['Notes']

    return(comments)