def combine_comments(comments):
    """
    Given a list of comments, or a comment submitted as a string, return a
    single line of text containing all of the comments.
    """
    if isinstance(comments, list):
        comments = [c if isinstance(c, str) else str(c) for c in comments]
    else:
        if not isinstance(comments, str):
            comments = [str(comments)]
        else:
            comments = [comments]
    return " ".join(comments).strip()