def make_a_string(item):
    """Convert tuple or list or None to a string. Important: elements in tuple or list are separated with ; (not ,)
    for compatibility with csv."""
    if isinstance(item, tuple) or isinstance(item, list):
        return ';'.join([str(i) for i in item])
    elif item is None:
        return 'None'
    else:
        return item