Print at most `limit` elements of list.

def _brief_print_list(lst, limit=7):
    """Print at most `limit` elements of list."""
    lst = list(lst)
    if len(lst) > limit:
        return _brief_print_list(lst[:limit//2], limit) + ', ..., ' + \
            _brief_print_list(lst[-limit//2:], limit)
    return ', '.join(["'%s'"%str(i) for i in lst])